feat: web variants use relay WS directly — no bridge needed

Updated all 3 web client variants to connect via the relay's new
WebSocket endpoint (/ws/room) instead of the wzp-web bridge.

index.html:
- Boot logic now creates the correct client class per variant
  (WZPPureClient, WZPHybridClient, or WZPFullClient)

wzp-full.js (Full WASM):
- Tries WebTransport first with 3s timeout
- Falls back to WebSocket if WT unavailable or relay lacks HTTP/3
- WS fallback sends raw PCM (same as pure), WASM FEC module still loaded
- When WT works: full encrypted + FEC pipeline over UDP datagrams

Pure + Hybrid variants already used /ws/room — no changes needed.

All JS syntax verified, 63 relay tests passing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/wzp-web/static/index.html

@@ -117,8 +117,9 @@ function wzpBoot() {
     var proto = location.protocol === 'https:' ? 'wss:' : 'ws:';
     var wsUrl = proto + '//' + location.host + '/ws/' + encodeURIComponent(room);
 
-    // Create client (currently always WZPPureClient; future: switch on variant)
-    client = new WZPPureClient({
+    // Create client based on selected variant
+    var variant = WZPCore.detectVariant();
+    var clientOpts = {
       wsUrl: wsUrl,
       room: room,
       onAudio: function(pcm) {
@@ -130,7 +131,17 @@ function wzpBoot() {
       onStats: function(stats) {
         WZPCore.updateStats(stats);
       },
-    });
+    };
+
+    if (variant === 'full' && typeof WZPFullClient !== 'undefined') {
+      // Full variant: add WebTransport URL, falls back to WS if WT unavailable
+      clientOpts.url = location.origin.replace('http', 'https');
+      client = new WZPFullClient(clientOpts);
+    } else if (variant === 'hybrid' && typeof WZPHybridClient !== 'undefined') {
+      client = new WZPHybridClient(clientOpts);
+    } else {
+      client = new WZPPureClient(clientOpts);
+    }
 
     try {
       await client.connect();