feat: Complete watchlist & auto-download system with UI

Implement comprehensive watchlist system with automatic episode detection
and downloading. Features include per-user watchlists, scheduler-based
periodic checks, and a modern web UI.

**Backend Components:**
- WatchlistManager: JSON-based storage with multi-tenant support
- EpisodeChecker: Detects and downloads new episodes automatically
- AutoDownloadScheduler: APScheduler-based periodic task execution
- Complete REST API for CRUD operations and scheduler control

**Frontend Components:**
- Modern watchlist page with dark theme and animations
- Real-time status updates and progress tracking
- Scheduler controls with next-run display
- Add anime directly from search results

**Models & Configuration:**
- WatchlistItem with status, quality, and auto-download settings
- WatchlistSettings for global configuration
- Per-user statistics and provider tracking

**API Endpoints:**
- GET/POST /api/watchlist - List and add items
- PUT/DELETE /api/watchlist/{id} - Update and delete
- POST /api/watchlist/{id}/check - Manual check trigger
- POST /api/watchlist/check-all - Check all due items
- GET/PUT /api/watchlist/settings - Global settings
- GET /api/watchlist/stats - Statistics
- GET/POST /api/watchlist/scheduler/* - Scheduler control

**Configuration Files:**
- config/watchlist.json - User watchlist data
- config/watchlist_settings.json - Global settings

Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>

static/js/watchlist.js

@@ -1,14 +1,13 @@
 /**
  * Watchlist management and auto-download UI
+ * Note: API_BASE is defined in api.js (loaded before this file)
  */
 
-const API_BASE = '/api';
-
 /**
  * Get user's watchlist
  */
 async function getWatchlist(status = null) {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -35,7 +34,7 @@ async function getWatchlist(status = null) {
  * Add anime to watchlist
  */
 async function addToWatchlist(animeData) {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -61,7 +60,7 @@ async function addToWatchlist(animeData) {
  * Update watchlist item
  */
 async function updateWatchlistItem(itemId, updateData) {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -86,7 +85,7 @@ async function updateWatchlistItem(itemId, updateData) {
  * Delete from watchlist
  */
 async function deleteFromWatchlist(itemId) {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -123,7 +122,7 @@ async function resumeWatchlistItem(itemId) {
  * Check specific anime for new episodes
  */
 async function checkWatchlistItem(itemId) {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -146,7 +145,7 @@ async function checkWatchlistItem(itemId) {
  * Check all watchlist items
  */
 async function checkAllWatchlistItems() {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -169,7 +168,7 @@ async function checkAllWatchlistItems() {
  * Get watchlist settings
  */
 async function getWatchlistSettings() {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -191,7 +190,7 @@ async function getWatchlistSettings() {
  * Update watchlist settings
  */
 async function updateWatchlistSettings(settings) {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -216,7 +215,7 @@ async function updateWatchlistSettings(settings) {
  * Get watchlist statistics
  */
 async function getWatchlistStats() {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -238,7 +237,7 @@ async function getWatchlistStats() {
  * Get scheduler status
  */
 async function getSchedulerStatus() {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -260,7 +259,7 @@ async function getSchedulerStatus() {
  * Start scheduler
  */
 async function startScheduler() {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }
@@ -283,7 +282,7 @@ async function startScheduler() {
  * Stop scheduler
  */
 async function stopScheduler() {
-    const token = localStorage.getItem('token');
+    const token = localStorage.getItem('auth_token');
     if (!token) {
         throw new Error('Not authenticated');
     }