Revert memory commit/push — gitignore life/ and memory/ instead

Agent memory files can contain secrets (API keys, credentials, infra
details). These must not be committed to git. Memory persists on the
pod's persistent volume. Git is for board-authored config only.

- Added life/ and memory/ back to .gitignore
- Removed git add/commit/push from CEO heartbeat sync (pull-only now)
- Removed auto-merge workflow (no longer needed)

Co-Authored-By: Paperclip <noreply@paperclip.ing>

ceo/HEARTBEAT.md

@@ -77,9 +77,7 @@ This repo (`/paperclip/privilegedescalation/agents`) is the canonical source of
 
     export GH_TOKEN=$(bash /paperclip/privilegedescalation/agents/get-github-token.sh)
     cd /paperclip/privilegedescalation/agents
-    git add -A
-    git diff --cached --quiet || git commit -m "agent: memory and runtime updates $(date -u +%Y-%m-%dT%H:%M:%SZ)"
-    git pull --rebase origin main && git push origin HEAD:refs/heads/agent-sync -f
+    git pull origin main
 
 #### 5b. Detect changes since last sync