Fix terminal slot review issues

packages/server/src/shared/messages.ts

@@ -2161,12 +2161,19 @@ export const CreateTerminalResponseSchema = z.object({
 
 export const SubscribeTerminalResponseSchema = z.object({
   type: z.literal("subscribe_terminal_response"),
-  payload: z.object({
-    terminalId: z.string(),
-    slot: z.number().int().min(0).max(255),
-    error: z.string().nullable(),
-    requestId: z.string(),
-  }),
+  payload: z.union([
+    z.object({
+      terminalId: z.string(),
+      slot: z.number().int().min(0).max(255),
+      error: z.null(),
+      requestId: z.string(),
+    }),
+    z.object({
+      terminalId: z.string(),
+      error: z.string(),
+      requestId: z.string(),
+    }),
+  ]),
 });
 
 export const KillTerminalResponseSchema = z.object({

packages/server/src/shared/terminal-stream-protocol.ts

@@ -84,7 +84,7 @@ export function decodeTerminalStreamFrame(bytes: Uint8Array): TerminalStreamFram
   }
   return {
     opcode,
-    slot: bytes[1] ?? 0,
+    slot: bytes[1],
     payload: bytes.subarray(2),
   };
 }