fix sidecar websocket: routes handler was intercepting upgrade requests

The Bun routes option matched "/" before fetch could handle the
WebSocket upgrade, so the API server could never connect. Moved
route handling into fetch after the upgrade check.

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

src/servers/sidecar/index.ts

@@ -203,22 +203,23 @@ const server = Bun.serve({
   port: PORT,
   hostname: '127.0.0.1',
 
-  routes: {
-    '/': () => new Response('process-sidecar'),
-    '/health': () => new Response(JSON.stringify({
-      status: 'ok',
-      uptime: Date.now() - startedAt,
-      piSessions: piManager.getAllSessions().length,
-      claudeSessions: claudeManager.getActiveSessionKeys().length,
-    }), { headers: { 'Content-Type': 'application/json' } }),
-  },
-
   fetch(req, server) {
     if (req.headers.get('upgrade') === 'websocket') {
       const ok = server.upgrade(req);
       if (!ok) return new Response('Upgrade failed', { status: 500 });
       return;
     }
+
+    const url = new URL(req.url);
+    if (url.pathname === '/') return new Response('process-sidecar');
+    if (url.pathname === '/health') {
+      return new Response(JSON.stringify({
+        status: 'ok',
+        uptime: Date.now() - startedAt,
+        piSessions: piManager.getAllSessions().length,
+        claudeSessions: claudeManager.getActiveSessionKeys().length,
+      }), { headers: { 'Content-Type': 'application/json' } });
+    }
     return new Response('Not found', { status: 404 });
   },