feat: implement collection library filter with WebSocket improvements and test coverage

This commit adds comprehensive functionality for filtering collections by library,
improves WebSocket real-time updates with user activity detection, and adds
extensive test coverage.

## Core Features

### Collection Library Filter
- Added library_id parameter to media-items search API
- Collections can now be filtered by specific library
- Toggle UI component for enabling/disabling library filter
- Default state is "checked" when library_id is present
- Consistent behavior across partial and fuzzy search modes

### WebSocket Auto-Reload Mitigation
- Added user activity detection to prevent disruptive page reloads
- Checks if user is actively typing in INPUT/TEXTAREA/SELECT elements
- Skips auto-reload when user is interacting with form elements
- Toast notifications still show for awareness
- Prevents data loss during editing operations

## Implementation Changes

### Backend
- internal/database/queries.sql.go: Added library filter support to search queries
- internal/handlers/media.go: Enhanced search with library_id parameter validation
- internal/handlers/collections.go: Updated collection handlers with library filtering
- internal/sync/websocket.go: Improved broadcast mechanism with user-scoped updates
- internal/router/frontend.go: Pass libraryID to collection templates

### Frontend
- templates/collections.templ: Added library filter toggle UI component
- web/src/collections.ts: TypeScript implementation with WebSocket integration
- templates/collections_templ.go: Generated template code

### Testing
- cmd/server/tests/search_test.go: Added TestCollectionSearchLibraryFilter
- cmd/server/tests/websocket_test.go: Added TestWebSocketUserScopedBroadcast
- New helper functions for creating libraries and media items via API
- Comprehensive test coverage for library filtering and user-scoped broadcasts

## API Documentation Updates

### Bruno Tests (Comprehensive Documentation)
- bruno/collections/*: Added detailed API documentation for all collection endpoints
- bruno/devices/*: Added device management and sync API documentation
- bruno/devices/kobo/api.yml: Kobo-specific sync protocol docs
- bruno/devices/koreader/api.yml: KOReader-specific sync protocol docs
- bruno/opds/*: Added OPDS feed and download endpoint documentation
- bruno/library/browse-folders.yml: Library folder browsing API docs

### New Bruno Tests
- bruno/media-items/Search All Libraries.yml: Test search without library filter
- bruno/media-items/Search Specific Library.yml: Test search with library filter
- bruno/media-items/Search Invalid Library ID.yml: Test error handling

## Documentation

- docs/developer/api/media-items/search_media_items.md: Updated with library_id parameter
- IMPLEMENTATION_COLLECTION_FIX.md: Comprehensive implementation guide with test scenarios

## Testing

### Integration Tests
- Library filter tests verify correct filtering across multiple libraries
- Invalid library_id tests ensure proper error handling
- WebSocket tests verify user-scoped broadcast behavior
- User A no longer receives User B's collection updates

### Manual Testing Scenarios
- Open collection in multiple tabs - updates propagate correctly
- Type in search box while another tab adds books - no disruptive reload
- Add/remove books from collection - toast notifications appear
- Toggle library filter - results update dynamically

## Technical Details

- WebSocket broadcasts are now user-scoped for privacy
- Active element detection uses tagName and contenteditable attributes
- Library ID validation uses UUID format checking
- Progressive enhancement maintained - page works without JavaScript
- All changes follow PROJECT_GUIDELINES.md conventions
- TypeScript only for frontend logic
- TailwindCSS only for styling
- Procedural programming style throughout

## Breaking Changes

None - all changes are additive and backward compatible.

templates/collections_templ.go

@@ -162,7 +162,7 @@ func Collection(user User, collections []CollectionData, errorMessage string) te
 	})
 }
 
-func CollectionDetail(user User, collection CollectionData, books []handlers.BookInfo) templ.Component {
+func CollectionDetail(user User, collection CollectionData, books []handlers.BookInfo, libraryID 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 {
@@ -323,7 +323,7 @@ func CollectionDetail(user User, collection CollectionData, books []handlers.Boo
 				return templ_7745c5c3_Err
 			}
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 30, "</div></div><div id=\"add-books-modal\" class=\"hidden fixed inset-0 z-50 flex items-center justify-center\" style=\"background-color: rgba(0, 0, 0, 0.7);\"><div class=\"card rounded-lg p-6 w-full max-w-2xl mx-4\" style=\"background-color: var(--bg-secondary); border-color: var(--border);\"><div class=\"flex justify-between items-center mb-6\"><h2 class=\"text-xl font-bold\" style=\"color: var(--text-primary)\">Add Books to Collection</h2><button onclick=\"hideAddBooksModal()\" class=\"p-2 hover:opacity-80 rounded\" style=\"color: var(--text-primary)\">✕</button></div><p class=\"mb-4\" style=\"color: var(--text-secondary)\">Search and select books to add to this collection.</p><div class=\"mb-4\"><input type=\"text\" id=\"book-search\" placeholder=\"Search books...\" class=\"w-full px-4 py-2 border rounded-lg\" style=\"background-color: var(--bg-primary); color: var(--text-primary); border-color: var(--border);\"></div><div id=\"book-results\" class=\"max-h-64 overflow-y-auto mb-4\"></div><div class=\"flex justify-end space-x-3\"><button type=\"button\" onclick=\"hideAddBooksModal()\" class=\"btn-secondary px-4 py-2 rounded-lg\">Cancel</button> <button type=\"button\" onclick=\"addSelectedBooks()\" class=\"btn-primary px-4 py-2 rounded-lg\">Add Selected Books</button></div></div></div><script>\n            let collectionId = '{ collection.ID }';\n            let selectedBooks = new Set();\n            let booksToRemove = new Set();\n            let allBooks = [\n                { range books }{\n                    {\n                        id: '{ book.MediaItemID }',\n                        title: '{ book.Title }',\n                        author: '{ book.Author }',\n                        cover: '{ book.CoverImagePath }'\n                    },\n                }{ end }\n            ];\n            let ws = null;\n\n            function backToCollections() {\n                window.location.href = '/collections';\n            }\n\n            function connectWebSocket() {\n                const protocol = window.location.protocol === 'https:' ? 'wss:' : 'ws:';\n                const wsUrl = `${protocol}//${window.location.host}/ws/sync`;\n\n                ws = new WebSocket(wsUrl);\n\n                ws.onopen = function() {\n                    console.log('WebSocket connected');\n                };\n\n                ws.onmessage = function(event) {\n                    const message = JSON.parse(event.data);\n\n                    if (message.type === 'collection_updated' && message.data.collection_id === collectionId) {\n                        showToast(`Collection updated: ${message.data.action} (${message.data.count} books)`, 'info');\n\n                        setTimeout(() => {\n                            location.reload();\n                        }, 1000);\n                    }\n                };\n\n                ws.onclose = function() {\n                    console.log('WebSocket disconnected, reconnecting in 5s...');\n                    setTimeout(connectWebSocket, 5000);\n                };\n\n                ws.onerror = function(error) {\n                    console.error('WebSocket error:', error);\n                };\n            }\n\n            connectWebSocket();\n\n            function filterCollectionBooks() {\n                const searchTerm = document.getElementById('collection-search').value.toLowerCase();\n                const booksContainer = document.getElementById('books-container');\n                const bookCards = booksContainer.children;\n\n                let visibleCount = 0;\n                for (let i = 0; i < bookCards.length; i++) {\n                    const card = bookCards[i];\n                    if (card.id === 'empty-state') continue;\n\n                    const title = card.querySelector('.font-semibold')?.textContent.toLowerCase() || '';\n                    const author = card.querySelector('.text-sm')?.textContent.toLowerCase() || '';\n\n                    const matches = title.includes(searchTerm) || author.includes(searchTerm);\n\n                    if (matches || searchTerm === '') {\n                        card.style.display = '';\n                        visibleCount++;\n                    } else {\n                        card.style.display = 'none';\n                    }\n                }\n            }\n\n            function showAddBooksModal() {\n                document.getElementById('add-books-modal').classList.remove('hidden');\n                selectedBooks.clear();\n                document.getElementById('book-results').innerHTML = '<p class=\"text-sm\" style=\"color: var(--text-secondary)\">Enter at least 2 characters to search.</p>';\n            }\n\n            function hideAddBooksModal() {\n                document.getElementById('add-books-modal').classList.add('hidden');\n                document.getElementById('book-search').value =Line truncated
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 30, "</div></div><div id=\"add-books-modal\" class=\"hidden fixed inset-0 z-50 flex items-center justify-center\" style=\"background-color: rgba(0, 0, 0, 0.7);\"><div class=\"card rounded-lg p-6 w-full max-w-2xl mx-4\" style=\"background-color: var(--bg-secondary); border-color: var(--border);\"><div class=\"flex justify-between items-center mb-6\"><h2 class=\"text-xl font-bold\" style=\"color: var(--text-primary)\">Add Books to Collection</h2><button onclick=\"hideAddBooksModal()\" class=\"p-2 hover:opacity-80 rounded\" style=\"color: var(--text-primary)\">✕</button></div><p class=\"mb-4\" style=\"color: var(--text-secondary)\">Search and select books to add to this collection.</p><!-- Library filter toggle - hidden by default, shown by JS when library_id present --><div id=\"library-filter-container\" class=\"mb-4 hidden\"><label class=\"flex items-center gap-2 text-sm\" style=\"color: var(--text-secondary);\"><input type=\"checkbox\" id=\"filter-by-library\" class=\"w-4 h-4\" onchange=\"searchBooksForCollection()\"> <span>Only show books from this library</span></label></div><div class=\"mb-4\"><input type=\"text\" id=\"book-search\" placeholder=\"Search books...\" class=\"w-full px-4 py-2 border rounded-lg\" style=\"background-color: var(--bg-primary); color: var(--text-primary); border-color: var(--border);\"></div><div id=\"book-results\" class=\"max-h-64 overflow-y-auto mb-4\"></div><div class=\"flex justify-end space-x-3\"><button type=\"button\" onclick=\"hideAddBooksModal()\" class=\"btn-secondary px-4 py-2 rounded-lg\">Cancel</button> <button type=\"button\" onclick=\"addSelectedBooks()\" class=\"btn-primary px-4 py-2 rounded-lg\">Add Selected Books</button></div></div></div></body><div id=\"collection-data\" data-id=\"{collection.ID}\" data-library-id=\"{ libraryID }\" style=\"display: none;\"></div><!-- Include compiled TypeScript --><script src=\"/static/collections.js\"></script></html>")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}