fix: dedup intermediate/final, filter long descriptions, update SDKs

- Track lastIntermediateText to prevent duplicate Discord delivery
  when same text arrives as both intermediate and final
- Filter task_progress descriptions >80 chars (AI summaries)
- Mark completed subagents with ✅ instead of removing
- Update claude-agent-sdk 0.2.76→0.2.81, codex 0.115→0.116

runners/codex-runner/package.json

@@ -9,7 +9,7 @@
     "start": "node dist/index.js"
   },
   "dependencies": {
-    "@openai/codex": "^0.115.0"
+    "@openai/codex": "^0.116.0"
   },
   "devDependencies": {
     "@types/node": "^22.10.7",