fix: pass gateway token via URL query parameter

Gateway may validate auth during HTTP upgrade before WebSocket
messages can be sent.

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

plugin/index.ts

@@ -212,7 +212,9 @@ export default {
             reject(new Error('Gateway connection timeout'));
           }, 15000);
 
-          const client = new (globalThis as any).WebSocket(gatewayUrl);
+          // Pass token via Authorization header in the upgrade request
+          const wsUrl = gwToken ? `${gatewayUrl}?token=${encodeURIComponent(gwToken)}` : gatewayUrl;
+          const client = new (globalThis as any).WebSocket(wsUrl);
 
           client.onerror = (err: any) => {
             clearTimeout(timeout);