revert(call-omo-agent): remove metis/momus from ALLOWED_AGENTS

call_omo_agent is for lightweight exploration agents (explore, librarian).
metis/momus are consultation agents that should be invoked via delegate_task.

Reverts part of #1462 that incorrectly added metis/momus to call_omo_agent.

Author: code-yeongyu

src/tools/call-omo-agent/constants.ts

@@ -1,6 +1,6 @@
-export const ALLOWED_AGENTS = ["explore", "librarian", "metis", "momus"] as const
+export const ALLOWED_AGENTS = ["explore", "librarian"] as const
 
-export const CALL_OMO_AGENT_DESCRIPTION = `Spawn explore/librarian/metis/momus agent. run_in_background REQUIRED (true=async with task_id, false=sync).
+export const CALL_OMO_AGENT_DESCRIPTION = `Spawn explore/librarian agent. run_in_background REQUIRED (true=async with task_id, false=sync).
 
 Available: {agents}
 

src/tools/call-omo-agent/tools.ts

@@ -47,7 +47,7 @@ export function createCallOmoAgent(
       prompt: tool.schema.string().describe("The task for the agent to perform"),
       subagent_type: tool.schema
         .string()
-        .describe("The type of specialized agent to use for this task (explore, librarian, metis, or momus)"),
+        .describe("The type of specialized agent to use for this task (explore or librarian only)"),
       run_in_background: tool.schema
         .boolean()
         .describe("REQUIRED. true: run asynchronously (use background_output to get results), false: run synchronously and wait for completion"),