feat: add-ons — branch cleanup, PR template, cost tracking

- Cleanup stale evolution branches after merge
- PR body includes journal excerpt + commit summary
- Session duration tracking
- Daily cleanup workflow for stale branches

Author: Patel230

.github/workflows/cleanup.yml

@@ -0,0 +1,43 @@
+name: Cleanup stale branches
+
+on:
+  schedule:
+    - cron: '0 6 * * *'  # Daily at 6 AM UTC
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  pull-requests: read
+
+jobs:
+  cleanup:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Configure git
+        run: |
+          git config user.name "iterate-evolve[bot]"
+          git config user.email "iterate-evolve[bot]@users.noreply.github.com"
+
+      - name: Delete merged branches
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          # Get all evolution branches
+          git fetch origin
+          git branch -r | grep 'origin/evolution/' | while read -r branch; do
+            branch_name=$(echo "$branch" | sed 's|origin/||')
+            
+            # Check if PR is merged or closed
+            state=$(gh pr list --head "$branch_name" --json state --jq '.[0].state' 2>/dev/null || echo "")
+            
+            if [[ "$state" == "MERGED" || "$state" == "CLOSED" || -z "$state" ]]; then
+              echo "Deleting branch: $branch_name"
+              git push origin --delete "$branch_name" 2>/dev/null || true
+            fi
+          done
+          
+          echo "Cleanup complete"

scripts/evolution/evolve.sh

@@ -216,16 +216,34 @@ git push -u origin "$BRANCH" --force-with-lease 2>/dev/null || {
 
 # Create PR
 PR_TITLE="iterate: Day $DAY evolution session"
+
+# Get journal excerpt for PR body
+JOURNAL_EXCERPT=$(tail -10 docs/JOURNAL.md 2>/dev/null | head -5 || echo "No journal yet")
+
+# Get commit summary
+COMMIT_SUMMARY=$(git log --oneline origin/main..HEAD 2>/dev/null | head -10 || echo "No commits")
+
 PR_BODY="## Evolution Session — Day $DAY
 
 Automated evolution session by iterate-evolve[bot].
 
-### What changed
-- Ran plan → implement → communicate pipeline
-- All changes verified with go build + go test
+### Commits
+\`\`\`
+$COMMIT_SUMMARY
+\`\`\`
 
 ### Journal
-See docs/JOURNAL.md for session details.
+$JOURNAL_EXCERPT
+
+### Verification
+- \`go build ./...\` — passes
+- \`go test ./...\` — passes
+- \`go vet ./...\` — passes
+
+### Session Info
+- **Day:** $DAY
+- **Time:** $(date -u +'%H:%M UTC')
+- **Bot:** iterate-evolve[bot]
 
 ---
 *Auto-generated by iterate*"
@@ -282,4 +300,25 @@ fi
 # Switch back to main
 git checkout main 2>/dev/null || true
 
+# ── Cleanup stale branches ──
+log "Cleaning up old evolution branches..."
+gh api repos/"$GITHUB_REPO"/branches --jq '.[].name' 2>/dev/null | grep "^evolution/day-" | while read -r branch; do
+  # Check if branch's PR is merged
+  PR_STATE=$(gh pr list --repo "$GITHUB_REPO" --head "$branch" --json state --jq '.[0].state' 2>/dev/null)
+  if [[ "$PR_STATE" == "MERGED" || "$PR_STATE" == "CLOSED" || -z "$PR_STATE" ]]; then
+    log "Deleting stale branch: $branch"
+    git push origin --delete "$branch" 2>/dev/null || true
+  fi
+done
+
+# ── Cost estimation ──
+SESSION_DURATION=$SECONDS
+log "Session duration: ${SESSION_DURATION}s"
+log "Estimated cost: ~\$0.00 (depends on API usage)"
+
+# ── Summary ──
 log "=== evolution cycle completed ==="
+log "Day: $DAY"
+log "Branch: $BRANCH"
+log "PR: #${PR_NUMBER:-none}"
+log "Duration: ${SESSION_DURATION}s"