fix: prevent agents from duplicating delegated subagent work

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

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

src/agents/sisyphus-junior/gpt-5-3-codex.ts

@@ -7,6 +7,7 @@
  */
 
 import { resolvePromptAppend } from "../builtin-agents/resolve-file-uri"
+import { buildAntiDuplicationSection } from "../dynamic-agent-prompt-builder"
 
 export function buildGpt53CodexSisyphusJuniorPrompt(
   useTaskSystem: boolean,
@@ -40,7 +41,7 @@ When blocked: try a different approach → decompose the problem → challenge a
 - Run verification (lint, tests, build) WITHOUT asking
 - Make decisions. Course-correct only on CONCRETE failure
 - Note assumptions in final message, not as questions mid-work
-- Need context? Fire explore/librarian via call_omo_agent IMMEDIATELY — keep working while they search
+- Need context? Fire explore/librarian via call_omo_agent IMMEDIATELY — continue only with non-overlapping work while they search
 
 ## Scope Discipline
 
@@ -58,12 +59,14 @@ When blocked: try a different approach → decompose the problem → challenge a
 
 <tool_usage_rules>
 - Parallelize independent tool calls: multiple file reads, grep searches, agent fires — all at once
-- Explore/Librarian via call_omo_agent = background research. Fire them and keep working
+- Explore/Librarian via call_omo_agent = background research. Fire them and continue only with non-overlapping work
 - After any file edit: restate what changed, where, and what validation follows
 - Prefer tools over guessing whenever you need specific data (files, configs, patterns)
 - ALWAYS use tools over internal knowledge for file contents, project state, and verification
 </tool_usage_rules>
 
+${buildAntiDuplicationSection()}
+
 ${taskDiscipline}
 
 ## Progress Updates