feat: Add torch MCP tools for multi-browser control

- Add torchHandlers.ts with 5 tools:
  - list_torch_clients: list connected browsers with metadata
  - get_torch_status: show current torch holder
  - transfer_torch: transfer control to another browser
  - request_torch: request MCP control
  - release_torch: release MCP control
- Add 'transfer' message type to server torch-handler
- Add torch category to all pages
- Export helper functions from torch.ts

server/services/handlers/torch-handler.ts

@@ -102,6 +102,43 @@ export function handleTorchMessage(ws: any, data: any, broadcast: (message: stri
       }
       break
     }
+
+    case 'transfer': {
+      // Transfer torch to a specific client (only if sender has torch or no one has it)
+      const targetId = data.targetId
+      if (!targetId) {
+        ws.send(JSON.stringify({ type: 'error', message: 'targetId required' }))
+        break
+      }
+
+      // Check if target exists
+      let targetExists = false
+      for (const [, c] of torchClients) {
+        if (c.id === targetId) {
+          targetExists = true
+          break
+        }
+      }
+
+      if (!targetExists) {
+        ws.send(JSON.stringify({ type: 'error', message: 'Target client not found' }))
+        break
+      }
+
+      // Only allow transfer if sender has torch or no one has it
+      if (torchHolderId !== null && torchHolderId !== client.id) {
+        ws.send(JSON.stringify({ type: 'error', message: 'Cannot transfer - you do not have the torch' }))
+        break
+      }
+
+      const previousHolder = torchHolderId
+      torchHolderId = targetId
+
+      ws.send(JSON.stringify({ type: 'transferred', targetId }))
+      console.log(`[Torch] Transferred by ${client.id}: ${previousHolder} → ${targetId}`)
+      broadcastTorchState(broadcast)
+      break
+    }
   }
 }