feat(filters+ui): per-element author/publisher filters, playlist toggles, Up Next API, reorder UI, dashboard badges

Phases 4 + 5 of the metadata overhaul (plan §4, §5) plus §3 handler
wiring.

Filters (§4.1): author_filter/publisher_filter now match per-element
against the authors[]/publishers[] arrays — a co-authored book matches
any one of its authors — with comma-joined params acting as
OR-within-facet multi-select (string_to_array + cross unnest). Legacy
single-value params unchanged on the wire; series/genre/language
filters stay on their varchar columns; narrator filter already
per-element.

Collections API (§3.3-3.5): collection detail carries viewer +
hide_finished into the listing query and exposes up_next (visible-
library-enforced reading-queue head); PUT
/api/collections/:id/items/order (owner-only, full-order rewrite);
UpdateCollectionRequest gains hide_finished/show_up_next ([]
string last-value-wins for the hidden-false-sibling checkbox pattern)
merged server-side OVER stored view_settings so imported_from_series
provenance survives edits; EditCollectionModal renders the toggles
from view_settings.

Dashboard (§5.5): sections JSON carries is_playlist/complete
(dashboard.ts is the AGENTS-documented JSON-render exception; first
paint stays templ). Fully-read playlists render '✓ Playlist complete'
instead of an empty rail; imported playlists get a 📖 Playlist badge.

Frontend: book detail shows subtitle + full authors + Explicit badge;
edit modal gains subtitle, comma-separated authors/publishers (client-
split to arrays exactly like narrators), step=any series number,
explicit checkbox; collection book cards get playlist move ↑/↓ buttons
persisting the full order via the reorder endpoint (templ partial
re-render on failure — DOM order is client-local, API order is truth).

AGENTS.md gotcha #3 amended per plan §3.7: user collections are
dashboard sections by default; the show_on_dashboard premise is
retired.

Verified: full affected integration sweep green (pins widened for
up_next/is_playlist/complete — changelog entries in
docs/contract_pins.md); unit suite green; go build + templ + vite
green.

templates/book_detail.templ

@@ -63,7 +63,14 @@ templ BookDetail(user User, book handlers.MediaDetail, errorMessage string, tomb
 						<!-- Details -->
 						<div class="flex-1 min-w-0">
 							<h1 class="text-3xl md:text-4xl font-bold tracking-tight mb-2" style="color: var(--text-primary)">{ book.Title }</h1>
-							if book.Author.Valid && book.Author.String != "" {
+							if book.Subtitle.Valid && book.Subtitle.String != "" {
+								<p class="text-lg mb-2" style="color: var(--text-secondary)">{ book.Subtitle.String }</p>
+							}
+							if len(book.Authors) > 0 {
+								<h2 class="text-lg md:text-xl mb-5" style="color: var(--text-secondary)">
+									by { strings.Join(book.Authors, ", ") }
+								</h2>
+							} else if book.Author.Valid && book.Author.String != "" {
 								<h2 class="text-lg md:text-xl mb-5" style="color: var(--text-secondary)">
 									by { book.Author.String }
 								</h2>
@@ -184,6 +191,9 @@ templ BookDetail(user User, book handlers.MediaDetail, errorMessage string, tomb
 							}
 							<!-- Badges: series, direction, tags -->
 							<div class="flex flex-wrap items-center gap-2 mb-3">
+								if book.Explicit {
+									<span class="badge" style="border: 1px solid var(--border); color: var(--text-secondary);" title="Marked explicit in source metadata">Explicit</span>
+								}
 								if book.Series.Valid && book.Series.String != "" {
 									<a
 										href={ "/series/detail?name=" + url.QueryEscape(book.Series.String) + "&library_id=" + uuidToString(book.LibraryID) }

templates/book_detail_modals.templ

@@ -323,9 +323,13 @@ templ MetadataEditorModal(book handlers.MediaDetail) {
 								<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Title</label>
 								<input type="text" name="title" value={ book.Title } class="input" />
 							</div>
+							<div>
+								<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Subtitle</label>
+								<input type="text" name="subtitle" value={ textToString(book.Subtitle) } class="input" />
+							</div>
 							<div>
 								<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Author</label>
-								<input type="text" name="author" value={ textToString(book.Author) } class="input" />
+								<input type="text" name="authors" value={ authorsFormValue(book.Authors, textToString(book.Author)) } class="input" placeholder="Comma-separated names"/>
 							</div>
 							<div>
 								<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Description</label>
@@ -400,7 +404,7 @@ templ MetadataEditorModal(book handlers.MediaDetail) {
 						<div x-show="openSections.publication" x-transition class="p-4 space-y-3 border-t" style="border-color: var(--border);">
 							<div>
 								<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Publisher</label>
-								<input type="text" name="publisher" value={ textToString(book.Publisher) } class="input" />
+								<input type="text" name="publishers" value={ authorsFormValue(book.Publishers, textToString(book.Publisher)) } class="input" placeholder="Comma-separated publishers"/>
 							</div>
 							<div>
 								<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Date Published</label>
@@ -446,7 +450,7 @@ templ MetadataEditorModal(book handlers.MediaDetail) {
 							<div class="grid grid-cols-3 gap-3">
 								<div>
 									<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Number</label>
-									<input type="number" name="series_number"
+									<input type="number" name="series_number" step="any"
 										value={ fmtNumber(book.SeriesNumber.Float64) }
 										class="input" />
 								</div>
@@ -524,6 +528,12 @@ templ MetadataEditorModal(book handlers.MediaDetail) {
 										<span>Abridged edition</span>
 									</label>
 								</div>
+								<div>
+									<label class="flex items-center gap-2 text-sm" style="color: var(--text-primary);">
+										<input type="checkbox" name="explicit" checked={ book.Explicit } class="h-4 w-4 accent-current"/>
+										<span>Explicit content</span>
+									</label>
+								</div>
 								if book.AudioDuration() > 0 {
 									<div>
 										<label class="block text-xs font-semibold uppercase tracking-wide mb-1" style="color: var(--text-secondary);">Duration (scanned)</label>

templates/collection_modal.templ

@@ -72,6 +72,18 @@ templ CollectionModal(collection CollectionData) {
 							<button type="button" @click="selectColor('purple')" data-color="purple" class="w-8 h-8 rounded-full color-option bg-purple-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-purple-400" aria-label="Purple"></button>
 						</div>
 						<input type="hidden" name="color" id="collection-color" value={ collection.Color }/>
+						<div class="mb-4 space-y-2">
+							<label class="flex items-center gap-2 text-sm" style="color: var(--text-primary);">
+								<input type="hidden" name="hide_finished" value="false"/>
+								<input type="checkbox" name="hide_finished" value="true" checked={ collection.HideFinished } class="h-4 w-4 accent-current"/>
+								<span>Hide finished books (reading-queue mode)</span>
+							</label>
+							<label class="flex items-center gap-2 text-sm" style="color: var(--text-primary);">
+								<input type="hidden" name="show_up_next" value="false"/>
+								<input type="checkbox" name="show_up_next" value="true" checked={ collection.ShowUpNext } class="h-4 w-4 accent-current"/>
+								<span>Show Up Next strip</span>
+							</label>
+						</div>
 					</div>
 					<div class="flex justify-end space-x-3">
 						<button type="button" @click="closeCollectionModal()" class="btn btn-secondary">Cancel</button>

templates/collection_modal_templ.go

@@ -143,30 +143,56 @@ func CollectionModal(collection CollectionData) templ.Component {
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 13, "\"></div><div class=\"flex justify-end space-x-3\"><button type=\"button\" @click=\"closeCollectionModal()\" class=\"btn btn-secondary\">Cancel</button> <button type=\"submit\" class=\"btn btn-primary\">Update Collection</button></div></form>")
-			if templ_7745c5c3_Err != nil {
-				return templ_7745c5c3_Err
-			}
-		} else {
-			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 14, "<form hx-post=\"/api/collections\" hx-redirect=\"/collections\"><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Type</label><div class=\"grid grid-cols-2 gap-2\"><label class=\"relative cursor-pointer\"><input type=\"radio\" name=\"collection_type\" value=\"static\" checked class=\"peer sr-only\"><div class=\"p-3 rounded-lg border text-center peer-checked:border-blue-500\" style=\"background-color: var(--bg-primary); border-color: var(--border);\"><span class=\"font-semibold text-sm\" style=\"color: var(--text-primary)\">Static</span><p class=\"text-xs mt-1\" style=\"color: var(--text-secondary)\">Pick books by hand</p></div></label> <label class=\"relative cursor-pointer\"><input type=\"radio\" name=\"collection_type\" value=\"smart\" class=\"peer sr-only\"><div class=\"p-3 rounded-lg border text-center peer-checked:border-blue-500 peer-checked:ring-2 peer-checked:ring-blue-400\" style=\"background-color: var(--bg-primary); border-color: var(--border);\"><span class=\"font-semibold text-sm\" style=\"color: var(--text-primary)\">⚡ Smart</span><p class=\"text-xs mt-1\" style=\"color: var(--text-secondary)\">Match books by rules — always live</p></div></label></div></div><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Name</label> <input type=\"text\" name=\"name\" required class=\"input\" placeholder=\"My Reading List\"></div><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Description</label> <textarea name=\"description\" class=\"input\" placeholder=\"Optional description\" rows=\"3\"></textarea></div><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Icon</label> <input type=\"text\" id=\"icon-search\" class=\"input mb-2\" placeholder=\"Search or type emoji...\" maxlength=\"4\" @input=\"filterIcons($event.target.value)\" @focus=\"showAllIcons()\"> <input type=\"hidden\" name=\"icon\" id=\"collection-icon\" value=\"")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 13, "\"><div class=\"mb-4 space-y-2\"><label class=\"flex items-center gap-2 text-sm\" style=\"color: var(--text-primary);\"><input type=\"hidden\" name=\"hide_finished\" value=\"false\"> <input type=\"checkbox\" name=\"hide_finished\" value=\"true\" checked=\"")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
 			var templ_7745c5c3_Var8 string
-			templ_7745c5c3_Var8, templ_7745c5c3_Err = templ.ResolveAttributeValue(collection.Icon)
+			templ_7745c5c3_Var8, templ_7745c5c3_Err = templ.ResolveAttributeValue(collection.HideFinished)
 			if templ_7745c5c3_Err != nil {
-				return templ.Error{Err: templ_7745c5c3_Err, FileName: `collection_modal.templ`, Line: 135, Col: 83}
+				return templ.Error{Err: templ_7745c5c3_Err, FileName: `collection_modal.templ`, Line: 78, Col: 98}
 			}
 			_, 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, 15, "\"><div id=\"icon-grid\" class=\"grid grid-cols-8 gap-1 max-h-32 overflow-y-auto p-2 rounded-lg border\" style=\"background-color: var(--bg-primary); border-color: var(--border);\"></div></div><div class=\"mb-6\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Color</label><div class=\"flex gap-2\"><button type=\"button\" @click=\"selectColor('blue')\" data-color=\"blue\" class=\"w-8 h-8 rounded-full color-option bg-blue-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-blue-400\" aria-label=\"Blue\"></button> <button type=\"button\" @click=\"selectColor('red')\" data-color=\"red\" class=\"w-8 h-8 rounded-full color-option bg-red-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-red-400\" aria-label=\"Red\"></button> <button type=\"button\" @click=\"selectColor('yellow')\" data-color=\"yellow\" class=\"w-8 h-8 rounded-full color-option bg-yellow-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-yellow-400\" aria-label=\"Yellow\"></button> <button type=\"button\" @click=\"selectColor('green')\" data-color=\"green\" class=\"w-8 h-8 rounded-full color-option bg-green-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-green-400\" aria-label=\"Green\"></button> <button type=\"button\" @click=\"selectColor('purple')\" data-color=\"purple\" class=\"w-8 h-8 rounded-full color-option bg-purple-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-purple-400\" aria-label=\"Purple\"></button></div><input type=\"hidden\" name=\"color\" id=\"collection-color\" value=\"blue\"></div><div class=\"flex justify-end space-x-3\"><button type=\"button\" @click=\"closeCollectionModal()\" class=\"btn btn-secondary\">Cancel</button> <button type=\"submit\" class=\"btn btn-primary\">Create Collection</button></div></form>")
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 14, "\" class=\"h-4 w-4 accent-current\"> <span>Hide finished books (reading-queue mode)</span></label> <label class=\"flex items-center gap-2 text-sm\" style=\"color: var(--text-primary);\"><input type=\"hidden\" name=\"show_up_next\" value=\"false\"> <input type=\"checkbox\" name=\"show_up_next\" value=\"true\" checked=\"")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			var templ_7745c5c3_Var9 string
+			templ_7745c5c3_Var9, templ_7745c5c3_Err = templ.ResolveAttributeValue(collection.ShowUpNext)
+			if templ_7745c5c3_Err != nil {
+				return templ.Error{Err: templ_7745c5c3_Err, FileName: `collection_modal.templ`, Line: 83, Col: 95}
+			}
+			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var9)
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 15, "\" class=\"h-4 w-4 accent-current\"> <span>Show Up Next strip</span></label></div></div><div class=\"flex justify-end space-x-3\"><button type=\"button\" @click=\"closeCollectionModal()\" class=\"btn btn-secondary\">Cancel</button> <button type=\"submit\" class=\"btn btn-primary\">Update Collection</button></div></form>")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+		} else {
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 16, "<form hx-post=\"/api/collections\" hx-redirect=\"/collections\"><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Type</label><div class=\"grid grid-cols-2 gap-2\"><label class=\"relative cursor-pointer\"><input type=\"radio\" name=\"collection_type\" value=\"static\" checked class=\"peer sr-only\"><div class=\"p-3 rounded-lg border text-center peer-checked:border-blue-500\" style=\"background-color: var(--bg-primary); border-color: var(--border);\"><span class=\"font-semibold text-sm\" style=\"color: var(--text-primary)\">Static</span><p class=\"text-xs mt-1\" style=\"color: var(--text-secondary)\">Pick books by hand</p></div></label> <label class=\"relative cursor-pointer\"><input type=\"radio\" name=\"collection_type\" value=\"smart\" class=\"peer sr-only\"><div class=\"p-3 rounded-lg border text-center peer-checked:border-blue-500 peer-checked:ring-2 peer-checked:ring-blue-400\" style=\"background-color: var(--bg-primary); border-color: var(--border);\"><span class=\"font-semibold text-sm\" style=\"color: var(--text-primary)\">⚡ Smart</span><p class=\"text-xs mt-1\" style=\"color: var(--text-secondary)\">Match books by rules — always live</p></div></label></div></div><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Name</label> <input type=\"text\" name=\"name\" required class=\"input\" placeholder=\"My Reading List\"></div><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Description</label> <textarea name=\"description\" class=\"input\" placeholder=\"Optional description\" rows=\"3\"></textarea></div><div class=\"mb-4\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Icon</label> <input type=\"text\" id=\"icon-search\" class=\"input mb-2\" placeholder=\"Search or type emoji...\" maxlength=\"4\" @input=\"filterIcons($event.target.value)\" @focus=\"showAllIcons()\"> <input type=\"hidden\" name=\"icon\" id=\"collection-icon\" value=\"")
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			var templ_7745c5c3_Var10 string
+			templ_7745c5c3_Var10, templ_7745c5c3_Err = templ.ResolveAttributeValue(collection.Icon)
+			if templ_7745c5c3_Err != nil {
+				return templ.Error{Err: templ_7745c5c3_Err, FileName: `collection_modal.templ`, Line: 147, Col: 83}
+			}
+			_, templ_7745c5c3_Err = templ_7745c5c3_Buffer.WriteString(templ_7745c5c3_Var10)
+			if templ_7745c5c3_Err != nil {
+				return templ_7745c5c3_Err
+			}
+			templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 17, "\"><div id=\"icon-grid\" class=\"grid grid-cols-8 gap-1 max-h-32 overflow-y-auto p-2 rounded-lg border\" style=\"background-color: var(--bg-primary); border-color: var(--border);\"></div></div><div class=\"mb-6\"><label class=\"block text-xs font-semibold uppercase tracking-wide mb-2\" style=\"color: var(--text-secondary)\">Color</label><div class=\"flex gap-2\"><button type=\"button\" @click=\"selectColor('blue')\" data-color=\"blue\" class=\"w-8 h-8 rounded-full color-option bg-blue-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-blue-400\" aria-label=\"Blue\"></button> <button type=\"button\" @click=\"selectColor('red')\" data-color=\"red\" class=\"w-8 h-8 rounded-full color-option bg-red-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-red-400\" aria-label=\"Red\"></button> <button type=\"button\" @click=\"selectColor('yellow')\" data-color=\"yellow\" class=\"w-8 h-8 rounded-full color-option bg-yellow-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-yellow-400\" aria-label=\"Yellow\"></button> <button type=\"button\" @click=\"selectColor('green')\" data-color=\"green\" class=\"w-8 h-8 rounded-full color-option bg-green-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-green-400\" aria-label=\"Green\"></button> <button type=\"button\" @click=\"selectColor('purple')\" data-color=\"purple\" class=\"w-8 h-8 rounded-full color-option bg-purple-500 hover:ring-2 hover:ring-offset-2 hover:ring-offset-transparent hover:ring-purple-400\" aria-label=\"Purple\"></button></div><input type=\"hidden\" name=\"color\" id=\"collection-color\" value=\"blue\"></div><div class=\"flex justify-end space-x-3\"><button type=\"button\" @click=\"closeCollectionModal()\" class=\"btn btn-secondary\">Cancel</button> <button type=\"submit\" class=\"btn btn-primary\">Create Collection</button></div></form>")
 			if templ_7745c5c3_Err != nil {
 				return templ_7745c5c3_Err
 			}
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 16, "</div></div>")
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 18, "</div></div>")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}

templates/collections.templ

@@ -36,6 +36,12 @@ templ CollectionBooksGrid(collection CollectionData, books []handlers.BookInfo)
 												@change={ "toggleSelection(" + JSONArg(book.MediaItemID) + ")" }
 											/>
 										</label>
+										<div class="flex flex-col items-center gap-0.5 mt-1">
+											<button type="button" class="icon-btn text-xs" title="Move earlier (playlist order)"
+												@click={ "moveCollectionBook(" + JSONArg(book.MediaItemID) + ", -1)" }>↑</button>
+											<button type="button" class="icon-btn text-xs" title="Move later (playlist order)"
+												@click={ "moveCollectionBook(" + JSONArg(book.MediaItemID) + ", 1)" }>↓</button>
+										</div>
 									</div>
 								}
 								<div class="flex-1 min-w-0">

templates/types.go

@@ -31,6 +31,10 @@ type CollectionData struct {
 	Color       string
 	Icon        string
 	IsSystem    bool
+	// A2c §3.3: playlist toggles (static collections only). Hidden fields
+	// preserve the current values on submit; absent from the create form.
+	HideFinished bool
+	ShowUpNext   bool
 	// IsSmart marks rule-based ("dynamic") collections: membership is
 	// evaluated live at render, not stored in collection_items.
 	IsSmart bool

templates/utils.go

@@ -475,3 +475,13 @@ func LibraryTypeDisplayName(name string) string {
 func fmtNumber(f float64) string {
 	return strconv.FormatFloat(f, 'f', -1, 64)
 }
+
+// authorsFormValue prefills an editable comma-separated author/publisher
+// field: the array is the write truth; the legacy single value is the
+// fallback for rows predating the arrays.
+func authorsFormValue(arr []string, legacy string) string {
+	if len(arr) > 0 {
+		return strings.Join(arr, ", ")
+	}
+	return legacy
+}