feat(admin): add scan settings + system information to settings page

- Scanning section: auto-scan toggle (on/off) and poll interval input
  with HTMX form that updates system_settings table
- System Information section: surfaces all hardcoded constants
  (session duration, password policy, rate limits, worker pool,
  sync queue, tombstone TTL, OPDS page size, CORS, etc.)
- New ScanSettingsData type, ScanSettingsSection partial template
- New HTMX endpoint: PUT /admin/settings/scan
- registerAdminSettingsRoutes for scan settings HTMX CRUD
- Fix bookhoord→bookhoard import typo in admin_library.go

internal/router/admin_library.go

@@ -10,6 +10,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/google/uuid"
@@ -378,3 +379,39 @@ func getAdminStats(ctx context.Context, cfg *Config) templates.AdminStats {
 
 	return stats
 }
+
+func registerAdminSettingsRoutes(cfg *Config, frontendProtected *echo.Group) {
+	g := frontendProtected.Group("", handlers.AdminMiddleware)
+
+	g.PUT("/admin/settings/scan", func(c *echo.Context) error {
+		ctx := c.Request().Context()
+
+		autoScan := c.FormValue("auto_scan_enabled") == "true"
+		intervalStr := c.FormValue("scan_poll_interval_seconds")
+		interval, err := strconv.Atoi(intervalStr)
+		if err != nil || interval < 1 || interval > 3600 {
+			return c.HTML(http.StatusBadRequest, `<div class="text-sm" style="color: var(--status-danger);">Interval must be between 1 and 3600 seconds</div>`)
+		}
+
+		autoScanStr := "false"
+		if autoScan {
+			autoScanStr = "true"
+		}
+		_ = cfg.Queries.UpdateSystemSetting(ctx, database.UpdateSystemSettingParams{
+			SettingKey:   "auto_scan_enabled",
+			SettingValue: autoScanStr,
+		})
+		_ = cfg.Queries.UpdateSystemSetting(ctx, database.UpdateSystemSettingParams{
+			SettingKey:   "scan_poll_interval_seconds",
+			SettingValue: strconv.Itoa(interval),
+		})
+
+		scanSettings := templates.ScanSettingsData{
+			AutoScanEnabled:         autoScan,
+			ScanPollIntervalSeconds: interval,
+		}
+		var buf bytes.Buffer
+		_ = templates.ScanSettingsSection(scanSettings).Render(ctx, &buf)
+		return c.HTML(http.StatusOK, buf.String())
+	})
+}

internal/router/frontend.go

@@ -995,21 +995,37 @@ func registerFrontendRoutes(cfg *Config) {
 			return renderErrorPage(c, "Error loading user", "user_load_error")
 		}
 
+		ctx := c.Request().Context()
+
 		// Fetch current system configuration - just base_url
-		baseURL := cfg.getBaseURL(c.Request().Context())
+		baseURL := cfg.getBaseURL(ctx)
 
 		systemConfig := map[string]string{
 			"base_url":         baseURL,
 			"default_timezone": "UTC",
 		}
 
-		defaultTimezone, err := cfg.Queries.GetSystemTimezone(c.Request().Context())
+		defaultTimezone, err := cfg.Queries.GetSystemTimezone(ctx)
 		if err == nil && defaultTimezone != "" {
 			systemConfig["default_timezone"] = defaultTimezone
 		}
 
+		// Fetch scan settings
+		scanSettings := templates.ScanSettingsData{
+			AutoScanEnabled:         true,
+			ScanPollIntervalSeconds: 60,
+		}
+		if val, err := cfg.Queries.GetSystemSetting(ctx, "auto_scan_enabled"); err == nil {
+			scanSettings.AutoScanEnabled = val == "true"
+		}
+		if val, err := cfg.Queries.GetSystemSetting(ctx, "scan_poll_interval_seconds"); err == nil {
+			if n, err := strconv.Atoi(val); err == nil {
+				scanSettings.ScanPollIntervalSeconds = n
+			}
+		}
+
 		var buf bytes.Buffer
-		err = templates.AdminSettings(user, systemConfig, "").Render(c.Request().Context(), &buf)
+		err = templates.AdminSettings(user, systemConfig, scanSettings, "").Render(ctx, &buf)
 		if err != nil {
 			return err
 		}
@@ -1053,6 +1069,8 @@ func registerFrontendRoutes(cfg *Config) {
 
 	// Admin library HTMX endpoints
 	registerAdminLibraryRoutes(cfg, frontendProtected)
+	// Admin settings HTMX endpoints
+	registerAdminSettingsRoutes(cfg, frontendProtected)
 
 	// ============================================================================
 	// LEGACY API ROUTES (for backward compatibility)

templates/admin_settings.templ

@@ -1,6 +1,8 @@
 package templates
 
-templ AdminSettings(user User, systemConfig map[string]string, errorMessage string) {
+import "fmt"
+
+templ AdminSettings(user User, systemConfig map[string]string, scanSettings ScanSettingsData, errorMessage string) {
 	<!DOCTYPE html>
 	<html lang="en">
 		<head>
@@ -105,8 +107,115 @@ templ AdminSettings(user User, systemConfig map[string]string, errorMessage stri
 								<p><span class="font-medium uppercase tracking-wide text-xs" style="color: var(--text-secondary)">Device Sync:</span> { systemConfig["base_url"] }/api/sync</p>
 							</div>
 						</div>
+					@ScanSettingsSection(scanSettings)
+					<div class="mt-6 card p-6">
+						<div class="flex items-center gap-2 mb-4">
+							@Icon("info", "h-5 w-5 shrink-0")
+							<h3 class="text-lg font-semibold" style="color: var(--text-primary)">System Information</h3>
+						</div>
+						<p class="text-sm mb-4" style="color: var(--text-secondary)">These values are hardcoded and require a code change to modify.</p>
+						<div class="divide-y" style="--tw-divide-opacity:1;">
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Session Duration</span>
+								<span class="text-sm" style="color: var(--text-secondary)">7 days</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Password Requirements</span>
+								<span class="text-sm" style="color: var(--text-secondary)">8+ chars, upper/lower/number/special</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Login Lockout</span>
+								<span class="text-sm" style="color: var(--text-secondary)">5 attempts / 15 min</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Auth Rate Limit</span>
+								<span class="text-sm" style="color: var(--text-secondary)">10 requests/min</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Device Rate Limits</span>
+								<span class="text-sm" style="color: var(--text-secondary)">Sync 60/min, Progress 120/min, Metadata 30/min</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Sync Queue</span>
+								<span class="text-sm" style="color: var(--text-secondary)">Every 5s, batch of 50</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Annotation Tombstone TTL</span>
+								<span class="text-sm" style="color: var(--text-secondary)">30 days</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Worker Pool</span>
+								<span class="text-sm" style="color: var(--text-secondary)">3 workers, queue cap 100</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">OPDS Page Size</span>
+								<span class="text-sm" style="color: var(--text-secondary)">50 per page (max 200)</span>
+							</div>
+							<div class="flex justify-between items-center py-3" style="border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">Conversion Cache TTL</span>
+								<span class="text-sm" style="color: var(--text-secondary)">24 hours</span>
+							</div>
+							<div class="flex justify-between items-center py-3">
+								<span class="text-sm font-medium" style="color: var(--text-primary)">CORS Origins</span>
+								<span class="text-sm" style="color: var(--text-secondary)">*</span>
+							</div>
+						</div>
+					</div>
 				</div>
 		</main>
 	</body>
 	</html>
 }
+
+templ ScanSettingsSection(scanSettings ScanSettingsData) {
+	<div id="scan-settings-section" class="mt-6 card p-6">
+		<div class="flex items-center gap-2 mb-6">
+			@Icon("refresh", "h-5 w-5 shrink-0")
+			<h3 class="text-lg font-semibold" style="color: var(--text-primary)">Scanning</h3>
+		</div>
+		<form
+			hx-put="/admin/settings/scan"
+			hx-target="#scan-settings-section"
+			hx-swap="outerHTML"
+		>
+			<div class="space-y-4">
+				<div class="flex items-center justify-between gap-4">
+					<div>
+						<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary)">Auto-Scan</label>
+						<p class="text-sm" style="color: var(--text-secondary)">Watch libraries for file changes on startup</p>
+					</div>
+					<label class="relative inline-flex items-center cursor-pointer shrink-0">
+						<input
+							type="checkbox"
+							name="auto_scan_enabled"
+							value="true"
+							checked?={ scanSettings.AutoScanEnabled }
+							class="sr-only peer"
+						/>
+						<div class="w-11 h-6 rounded-full peer peer-checked:bg-brand transition-colors" style="background-color: color-mix(in srgb, var(--text-primary) 15%, transparent);"></div>
+						<div class="absolute left-0.5 top-0.5 bg-white rounded-full w-5 h-5 transition-transform peer-checked:translate-x-5"></div>
+					</label>
+				</div>
+				<div>
+					<label class="block text-xs font-semibold uppercase tracking-wide mb-2" style="color: var(--text-secondary)">Scan Interval (seconds)</label>
+					<input
+						type="number"
+						name="scan_poll_interval_seconds"
+						value={ fmt.Sprintf("%d", scanSettings.ScanPollIntervalSeconds) }
+						min="1"
+						max="3600"
+						class="input"
+						required
+					/>
+					<p class="text-sm mt-2" style="color: var(--text-secondary)">How often to poll libraries for changes (1–3600 seconds). Default: 60.</p>
+				</div>
+				<div class="flex justify-end">
+					<button type="submit" class="btn btn-primary">
+						@Icon("save", "h-4 w-4")
+						Save Scan Settings
+					</button>
+				</div>
+			</div>
+		</form>
+	</div>
+}

templates/admin_settings_templ.go

@@ -8,7 +8,9 @@ package templates
 import "github.com/a-h/templ"
 import templruntime "github.com/a-h/templ/runtime"
 
-func AdminSettings(user User, systemConfig map[string]string, errorMessage string) templ.Component {
+import "fmt"
+
+func AdminSettings(user User, systemConfig map[string]string, scanSettings ScanSettingsData, errorMessage string) templ.Component {
 	return templruntime.GeneratedTemplate(func(templ_7745c5c3_Input templruntime.GeneratedComponentInput) (templ_7745c5c3_Err error) {
 		templ_7745c5c3_W, ctx := templ_7745c5c3_Input.Writer, templ_7745c5c3_Input.Context
 		if templ_7745c5c3_CtxErr := ctx.Err(); templ_7745c5c3_CtxErr != nil {
@@ -65,7 +67,7 @@ func AdminSettings(user User, systemConfig map[string]string, errorMessage strin
 			var templ_7745c5c3_Var2 string
 			templ_7745c5c3_Var2, templ_7745c5c3_Err = templ.JoinStringErrs(errorMessage)
 			if templ_7745c5c3_Err != nil {
-				return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 28, Col: 28}
+				return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 30, Col: 28}
 			}
 			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var2))
 			if templ_7745c5c3_Err != nil {
@@ -91,7 +93,7 @@ func AdminSettings(user User, systemConfig map[string]string, errorMessage strin
 		var templ_7745c5c3_Var3 string
 		templ_7745c5c3_Var3, templ_7745c5c3_Err = templ.ResolveAttributeValue(systemConfig["base_url"])
 		if templ_7745c5c3_Err != nil {
-			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 42, Col: 42}
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 44, Col: 42}
 		}
 		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var3)
 		if templ_7745c5c3_Err != nil {
@@ -368,7 +370,7 @@ func AdminSettings(user User, systemConfig map[string]string, errorMessage strin
 		var templ_7745c5c3_Var4 string
 		templ_7745c5c3_Var4, templ_7745c5c3_Err = templ.JoinStringErrs(systemConfig["base_url"])
 		if templ_7745c5c3_Err != nil {
-			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 103, Col: 145}
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 105, Col: 145}
 		}
 		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var4))
 		if templ_7745c5c3_Err != nil {
@@ -381,7 +383,7 @@ func AdminSettings(user User, systemConfig map[string]string, errorMessage strin
 		var templ_7745c5c3_Var5 string
 		templ_7745c5c3_Var5, templ_7745c5c3_Err = templ.JoinStringErrs(systemConfig["base_url"])
 		if templ_7745c5c3_Err != nil {
-			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 104, Col: 144}
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 106, Col: 144}
 		}
 		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var5))
 		if templ_7745c5c3_Err != nil {
@@ -394,13 +396,97 @@ func AdminSettings(user User, systemConfig map[string]string, errorMessage strin
 		var templ_7745c5c3_Var6 string
 		templ_7745c5c3_Var6, templ_7745c5c3_Err = templ.JoinStringErrs(systemConfig["base_url"])
 		if templ_7745c5c3_Err != nil {
-			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 105, Col: 152}
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 107, Col: 152}
 		}
 		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ.EscapeString(templ_7745c5c3_Var6))
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 63, "/api/sync</p></div></div></div></main></body></html>")
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 63, "/api/sync</p></div></div>")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = ScanSettingsSection(scanSettings).Render(ctx, templ_7745c5c3_Buffer)
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 64, "<div class=\"mt-6 card p-6\"><div class=\"flex items-center gap-2 mb-4\">")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = Icon("info", "h-5 w-5 shrink-0").Render(ctx, templ_7745c5c3_Buffer)
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 65, "<h3 class=\"text-lg font-semibold\" style=\"color: var(--text-primary)\">System Information</h3></div><p class=\"text-sm mb-4\" style=\"color: var(--text-secondary)\">These values are hardcoded and require a code change to modify.</p><div class=\"divide-y\" style=\"--tw-divide-opacity:1;\"><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Session Duration</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">7 days</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Password Requirements</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">8+ chars, upper/lower/number/special</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Login Lockout</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">5 attempts / 15 min</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Auth Rate Limit</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">10 requests/min</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Device Rate Limits</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">Sync 60/min, Progress 120/min, Metadata 30/min</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Sync Queue</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">Every 5s, batch of 50</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Annotation Tombstone TTL</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">30 days</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Worker Pool</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">3 workers, queue cap 100</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">OPDS Page Size</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">50 per page (max 200)</span></div><div class=\"flex justify-between items-center py-3\" style=\"border-color: color-mix(in srgb, var(--text-primary) 7%, transparent);\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">Conversion Cache TTL</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">24 hours</span></div><div class=\"flex justify-between items-center py-3\"><span class=\"text-sm font-medium\" style=\"color: var(--text-primary)\">CORS Origins</span> <span class=\"text-sm\" style=\"color: var(--text-secondary)\">*</span></div></div></div></div></main></body></html>")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		return nil
+	})
+}
+
+func ScanSettingsSection(scanSettings ScanSettingsData) templ.Component {
+	return templruntime.GeneratedTemplate(func(templ_7745c5c3_Input templruntime.GeneratedComponentInput) (templ_7745c5c3_Err error) {
+		templ_7745c5c3_W, ctx := templ_7745c5c3_Input.Writer, templ_7745c5c3_Input.Context
+		if templ_7745c5c3_CtxErr := ctx.Err(); templ_7745c5c3_CtxErr != nil {
+			return templ_7745c5c3_CtxErr
+		}
+		templ_7745c5c3_Buffer, templ_7745c5c3_IsBuffer := templruntime.GetBuffer(templ_7745c5c3_W)
+		if !templ_7745c5c3_IsBuffer {
+			defer func() {
+				templ_7745c5c3_BufErr := templruntime.ReleaseBuffer(templ_7745c5c3_Buffer)
+				if templ_7745c5c3_Err == nil {
+					templ_7745c5c3_Err = templ_7745c5c3_BufErr
+				}
+			}()
+		}
+		ctx = templ.InitializeContext(ctx)
+		templ_7745c5c3_Var7 := templ.GetChildren(ctx)
+		if templ_7745c5c3_Var7 == nil {
+			templ_7745c5c3_Var7 = templ.NopComponent
+		}
+		ctx = templ.ClearChildren(ctx)
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 66, "<div id=\"scan-settings-section\" class=\"mt-6 card p-6\"><div class=\"flex items-center gap-2 mb-6\">")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = Icon("refresh", "h-5 w-5 shrink-0").Render(ctx, templ_7745c5c3_Buffer)
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 67, "<h3 class=\"text-lg font-semibold\" style=\"color: var(--text-primary)\">Scanning</h3></div><form hx-put=\"/admin/settings/scan\" hx-target=\"#scan-settings-section\" hx-swap=\"outerHTML\"><div class=\"space-y-4\"><div class=\"flex items-center justify-between gap-4\"><div><label class=\"block text-xs font-semibold uppercase tracking-wide mb-1\" style=\"color: var(--text-secondary)\">Auto-Scan</label><p class=\"text-sm\" style=\"color: var(--text-secondary)\">Watch libraries for file changes on startup</p></div><label class=\"relative inline-flex items-center cursor-pointer shrink-0\"><input type=\"checkbox\" name=\"auto_scan_enabled\" value=\"true\"")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		if scanSettings.AutoScanEnabled {
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 68, " checked")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 69, " class=\"sr-only peer\"><div class=\"w-11 h-6 rounded-full peer peer-checked:bg-brand transition-colors\" style=\"background-color: color-mix(in srgb, var(--text-primary) 15%, transparent);\"></div><div class=\"absolute left-0.5 top-0.5 bg-white rounded-full w-5 h-5 transition-transform peer-checked:translate-x-5\"></div></label></div><div><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Scan Interval (seconds)</label> <input type=\"number\" name=\"scan_poll_interval_seconds\" value=\"")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		var templ_7745c5c3_Var8 string
+		templ_7745c5c3_Var8, templ_7745c5c3_Err = templ.ResolveAttributeValue(fmt.Sprintf("%d", scanSettings.ScanPollIntervalSeconds))
+		if templ_7745c5c3_Err != nil {
+			return templ.Error{Err: templ_7745c5c3_Err, FileName: `templates/admin_settings.templ`, Line: 204, Col: 69}
+		}
+		_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var8)
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 70, "\" min=\"1\" max=\"3600\" class=\"input\" required><p class=\"text-sm mt-2\" style=\"color: var(--text-secondary)\">How often to poll libraries for changes (1–3600 seconds). Default: 60.</p></div><div class=\"flex justify-end\"><button type=\"submit\" class=\"btn btn-primary\">")
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = Icon("save", "h-4 w-4").Render(ctx, templ_7745c5c3_Buffer)
+		if templ_7745c5c3_Err != nil {
+			return templ_7745c5c3_Err
+		}
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 71, "Save Scan Settings</button></div></div></form></div>")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}

templates/types.go

@@ -66,6 +66,11 @@ type AdminStats struct {
 	DeviceCount  int
 }
 
+type ScanSettingsData struct {
+	AutoScanEnabled         bool
+	ScanPollIntervalSeconds int
+}
+
 type SeriesCardData struct {
 	Name          string
 	BookCount     int64