feat: Implement torch system via HTTP for multi-browser control

- Add /api/torch endpoints for torch state management
- Torch system uses HTTP polling instead of WebSocket
- Only browser with torch connects to MCP
- Other browsers disconnect and poll for torch state
- Auto-assign torch to first registered client
- Auto-reassign torch when holder disconnects

This approach requires no changes to WebMCP library.

frontend/src/services/webmcp.ts

@@ -1,5 +1,4 @@
 import { useCanvasStore } from '../stores/canvas'
-import { useTorchStore } from '../stores/torch'
 import { endpoints, isSecure, wsProtocol, hostname } from '../config/endpoints'
 
 // WebMCP HTTP API base for direct token requests
@@ -118,43 +117,6 @@ function setupEventHandlers() {
       updateConnectionInfo()
     })
   )
-
-  // Torch events
-  const torchStore = useTorchStore()
-
-  eventUnsubscribers.push(
-    webmcpInstance.on('clientId', (data: { id: string }) => {
-      console.log('[WebMCP] Client ID assigned:', data.id)
-      torchStore.setClientId(data.id)
-    })
-  )
-
-  eventUnsubscribers.push(
-    webmcpInstance.on('torchUpdate', (data: { holderId: string | null; clients: any[] }) => {
-      console.log('[WebMCP] Torch state updated:', data.holderId)
-      torchStore.setClients(data.clients)
-    })
-  )
-
-  eventUnsubscribers.push(
-    webmcpInstance.on('torchGranted', () => {
-      console.log('[WebMCP] Torch granted!')
-      torchStore.setRequesting(false)
-    })
-  )
-
-  eventUnsubscribers.push(
-    webmcpInstance.on('torchDenied', (data: { reason: string }) => {
-      console.warn('[WebMCP] Torch denied:', data.reason)
-      torchStore.setRequesting(false)
-    })
-  )
-
-  eventUnsubscribers.push(
-    webmcpInstance.on('torchReleased', () => {
-      console.log('[WebMCP] Torch released')
-    })
-  )
 }
 
 function updateConnectionInfo() {