feat(agents): enable call_omo_agent for Sisyphus-Junior subagents

Allow Sisyphus-Junior (category-based tasks) to spawn explore/librarian
agents via call_omo_agent for research capabilities.

Changes:
- Remove call_omo_agent from BLOCKED_TOOLS in sisyphus-junior.ts
- Update prompt to show ALLOWED status for call_omo_agent
- Remove global call_omo_agent blocking in config-handler.ts
- Keep blocking for orchestrator-sisyphus (use sisyphus_task instead)
- Keep runtime recursion prevention in index.ts for explore/librarian

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/plugin-handlers/config-handler.ts

@@ -283,19 +283,11 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
     config.tools = {
       ...(config.tools as Record<string, unknown>),
       "grep_app_*": false,
-      call_omo_agent: false,
     };
 
-    if (agentResult.explore) {
-      agentResult.explore.tools = {
-        ...agentResult.explore.tools,
-        call_omo_agent: false,
-      };
-    }
     if (agentResult.librarian) {
       agentResult.librarian.tools = {
         ...agentResult.librarian.tools,
-        call_omo_agent: false,
         "grep_app_*": true,
       };
     }
@@ -303,7 +295,6 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
       agentResult["multimodal-looker"].tools = {
         ...agentResult["multimodal-looker"].tools,
         task: false,
-        call_omo_agent: false,
         look_at: false,
       };
     }