Simplify service worker: stop intercepting content requests

The SW was causing "unexpected error" on video/image fetches due to
range request handling, opaque response caching, and stale SW races.

Fix: SW now ONLY caches player page + socket.io JS for offline boot.
Content files are left to browser native HTTP cache (server already
sets Cache-Control: public, max-age=2592000, immutable).

Also: auto-reload player when new SW activates so deploys take effect
immediately without manual hard refresh.

Bumped cache to v5 — activate purges all old caches (including the
broken rd-content-v1 content cache).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/player/index.html

@@ -952,10 +952,21 @@
 
     // Register service worker for offline content caching
     if ('serviceWorker' in navigator) {
-      navigator.serviceWorker.register('/player/sw.js').then(
-        () => console.log('Service Worker registered'),
-        (err) => console.warn('SW registration failed:', err)
-      );
+      navigator.serviceWorker.register('/player/sw.js').then(reg => {
+        console.log('Service Worker registered');
+        // When a new SW activates, reload so the fresh code takes effect immediately
+        reg.addEventListener('updatefound', () => {
+          const newWorker = reg.installing;
+          if (newWorker) {
+            newWorker.addEventListener('statechange', () => {
+              if (newWorker.state === 'activated' && navigator.serviceWorker.controller) {
+                console.log('New Service Worker activated — reloading for fresh code');
+                location.reload();
+              }
+            });
+          }
+        });
+      }, (err) => console.warn('SW registration failed:', err));
     }
 
     // ==================== Keyboard shortcuts ====================

server/player/sw.js

@@ -1,61 +1,29 @@
-const CACHE_NAME = 'rd-player-v4';
-const CONTENT_CACHE = 'rd-content-v1';
+const CACHE_NAME = 'rd-player-v5';
 
 // Install: skip waiting to activate immediately
 self.addEventListener('install', (event) => {
   self.skipWaiting();
 });
 
-// Activate: clean old caches, claim clients
+// Activate: clean old caches (including old content cache), claim clients
 self.addEventListener('activate', (event) => {
   event.waitUntil(
     caches.keys().then(keys => Promise.all(
-      keys.filter(k => k !== CACHE_NAME && k !== CONTENT_CACHE).map(k => caches.delete(k))
+      keys.filter(k => k !== CACHE_NAME).map(k => caches.delete(k))
     )).then(() => self.clients.claim())
   );
 });
 
-// Fetch handler
+// Fetch handler — ONLY cache player page and static assets.
+// Content files (/uploads/content/) are NOT intercepted — the server sets
+// Cache-Control: public, max-age=2592000, immutable which lets the browser
+// cache them natively without SW complications (range requests, opaque
+// responses, video seeking, etc.)
 self.addEventListener('fetch', (event) => {
-  const url = new URL(event.request.url);
-
-  // Only handle GET requests — let POST/PUT/DELETE pass through
+  // Only handle GET requests
   if (event.request.method !== 'GET') return;
 
-  // Content files (videos, images): cache-first for offline playback
-  if (url.pathname.startsWith('/uploads/content/')) {
-    // Skip range requests (video seeking) — serve from network, don't cache partial responses
-    if (event.request.headers.get('range')) {
-      return; // Let the browser handle range requests directly
-    }
-
-    event.respondWith(
-      caches.open(CONTENT_CACHE).then(cache =>
-        cache.match(event.request, { ignoreSearch: true }).then(cached => {
-          if (cached) return cached;
-          return fetch(event.request).then(response => {
-            // Only cache successful, complete (non-opaque) responses
-            if (response.ok && response.status === 200 && response.type !== 'opaque') {
-              cache.put(event.request, response.clone());
-            }
-            return response;
-          }).catch(() => {
-            return new Response('Content unavailable offline', {
-              status: 503,
-              statusText: 'Service Unavailable',
-              headers: { 'Content-Type': 'text/plain' }
-            });
-          });
-        })
-      ).catch(() => {
-        // Cache API itself failed — fall through to network
-        return fetch(event.request).catch(() =>
-          new Response('Offline', { status: 503, headers: { 'Content-Type': 'text/plain' } })
-        );
-      })
-    );
-    return;
-  }
+  const url = new URL(event.request.url);
 
   // Player page and static assets: network-first, fall back to cache
   if (url.pathname.startsWith('/player') || url.pathname === '/socket.io/socket.io.js') {
@@ -79,6 +47,6 @@ self.addEventListener('fetch', (event) => {
     return;
   }
 
-  // Everything else: network only, don't intercept failures
-  // (Returning without calling event.respondWith lets the browser handle it natively)
+  // Everything else (content files, API calls, etc.): don't intercept.
+  // Returning without event.respondWith lets the browser handle it natively.
 });