Add user theme support and migrate frontend to HTMX templates

- Add theme column to users table with default 'tokyo-night'
- Update all user queries to include theme field
- Add ListUsers and UpdateUserTheme database queries
- Update auth handlers to support HTMX form submissions and JSON API
- Add ListUsers API endpoint
- Replace embedded static files with Go templates
- Update Dockerfile to copy templates directory
- Redesign index.html with inline styles and HTMX forms
- Update Bruno API testing requests for auth endpoints

backend/cmd/server/main.go

@@ -4,12 +4,10 @@ import (
 	"bookmann/internal/config"
 	"bookmann/internal/database"
 	"bookmann/internal/handlers"
-	"embed"
+	"html/template"
+	"io"
 	"log"
-	"mime"
 	"net/http"
-	"path/filepath"
-	"strings"
 
 	"github.com/go-playground/validator/v10"
 	jwtgo "github.com/golang-jwt/jwt"
@@ -17,8 +15,13 @@ import (
 	"github.com/labstack/echo/v4/middleware"
 )
 
-//go:embed static/*
-var staticFS embed.FS
+type TemplateRenderer struct {
+	templates *template.Template
+}
+
+func (t *TemplateRenderer) Render(w io.Writer, name string, data interface{}, c echo.Context) error {
+	return t.templates.ExecuteTemplate(w, name, data)
+}
 
 // CustomValidator wraps the go-playground validator
 type CustomValidator struct {
@@ -45,6 +48,12 @@ func main() {
 	// Set up validator
 	e.Validator = &CustomValidator{validator: validator.New()}
 
+	// Set up templates
+	renderer := &TemplateRenderer{
+		templates: template.Must(template.ParseGlob("templates/*.html")),
+	}
+	e.Renderer = renderer
+
 	// Middleware
 	e.Use(middleware.Logger())
 	e.Use(middleware.Recover())
@@ -69,42 +78,20 @@ func main() {
 	// Protected routes
 	protected := e.Group("/api", jwtMiddleware)
 	protected.GET("/auth/profile", auth.GetProfile)
+	protected.GET("/users", auth.ListUsers)
 
 	// Routes
 	handlers.SetupRoutes(protected, queries)
 
-	// Serve static files with SPA fallback from embedded FS
-	e.GET("/*", func(c echo.Context) error {
-		path := c.Request().URL.Path
-		if strings.HasPrefix(path, "/api") {
-			return c.String(http.StatusNotFound, "Not found")
-		}
-		// Try to serve the file from embedded FS
-		filePath := "static" + path
-		if file, err := staticFS.Open(filePath); err == nil {
-			defer file.Close()
-			contentType := mime.TypeByExtension(filepath.Ext(filePath))
-			if contentType == "" {
-				contentType = "application/octet-stream"
-			}
-			return c.Stream(http.StatusOK, contentType, file)
-		}
-		// Try .html extension
-		htmlPath := filePath + ".html"
-		if file, err := staticFS.Open(htmlPath); err == nil {
-			defer file.Close()
-			return c.Stream(http.StatusOK, "text/html", file)
-		}
-		// Try /index.html
-		indexPath := filePath + "/index.html"
-		if file, err := staticFS.Open(indexPath); err == nil {
-			defer file.Close()
-			return c.Stream(http.StatusOK, "text/html", file)
-		}
-		// Fallback to index.html
-		file, _ := staticFS.Open("static/index.html")
-		defer file.Close()
-		return c.Stream(http.StatusOK, "text/html", file)
+	// Page routes
+	e.GET("/", func(c echo.Context) error {
+		return c.Render(http.StatusOK, "index.html", nil)
+	})
+	e.GET("/login", func(c echo.Context) error {
+		return c.Render(http.StatusOK, "login.html", nil)
+	})
+	e.GET("/register", func(c echo.Context) error {
+		return c.Render(http.StatusOK, "register.html", nil)
 	})
 
 	// Start server