fix: supervisor should clean up stale PHASE:escalate files for closed issues (#664)

Add auto-cleanup to supervisor/preflight.sh: PHASE:escalate files whose
parent issue/PR is confirmed closed (via Forge API) are deleted after a
24h grace period. Cleanup results appear in the preflight output for
journal logging by the supervisor formula.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

formulas/run-supervisor.toml

@@ -28,9 +28,12 @@ The pre-flight metrics have already been collected by supervisor/preflight.sh
 and injected into your prompt above. Review them now.
 
 1. Read the injected metrics data carefully (System Resources, Docker,
-   Active Sessions, Phase Files, Lock Files, Agent Logs, CI Pipelines,
+   Active Sessions, Phase Files, Stale Phase Cleanup, Lock Files, Agent Logs,
-   Open PRs, Issue Status, Stale Worktrees, Pending Escalations,
+   CI Pipelines, Open PRs, Issue Status, Stale Worktrees, Pending Escalations,
    Escalation Replies).
+   Note: preflight.sh auto-removes PHASE:escalate files for closed issues
+   (24h grace period). Check the "Stale Phase Cleanup" section for any
+   files cleaned or in grace period this run.
 
 2. If there are escalation replies from Matrix (human messages), note them —
    you will act on them in the decide-actions step.
@@ -68,6 +71,8 @@ Categorize every finding from the metrics into priority levels.
 - Pipeline stalled: backlog issues exist but no agent ran for > 20min
 - Dev-agent blocked: last N polls all report "no ready issues"
 - Dev/action sessions in PHASE:escalate for > 24h (escalation timeout)
+  (Note: PHASE:escalate files for closed issues are auto-cleaned by preflight;
+  this check covers escalations where the issue is still open)
 
 ### P3 — Factory degraded
 - PRs stale: CI finished >20min ago AND no git push to the PR branch since CI completed
@@ -119,6 +124,10 @@ For each finding from the health assessment, decide and execute an action.
   cd "$PROJECT_REPO_ROOT"
   git checkout "$PRIMARY_BRANCH" 2>/dev/null
 
+**P4 Stale PHASE:escalate files (closed issues):**
+  Already handled by preflight.sh auto-cleanup. Check "Stale Phase Cleanup"
+  in the metrics for results. Log any cleanups in the journal.
+
 **P4 Stale worktrees:**
   git -C "$PROJECT_REPO_ROOT" worktree remove --force /tmp/stale-worktree 2>/dev/null
   git -C "$PROJECT_REPO_ROOT" worktree prune 2>/dev/null

supervisor/preflight.sh

@@ -68,6 +68,52 @@ done
 [ "$_found_phase" = false ] && echo "  None"
 echo ""
 
+# ── Stale Phase Cleanup ─────────────────────────────────────────────────
+# Auto-remove PHASE:escalate files whose parent issue/PR is confirmed closed.
+# Grace period: 24h after issue closure to avoid race conditions.
+
+echo "## Stale Phase Cleanup"
+_cleaned_any=false
+for _pf in /tmp/*-session-*.phase; do
+  [ -f "$_pf" ] || continue
+  _phase_line=$(head -1 "$_pf" 2>/dev/null || echo "")
+  # Only target PHASE:escalate files
+  case "$_phase_line" in
+    PHASE:escalate*) ;;
+    *) continue ;;
+  esac
+  # Extract issue number: *-session-{PROJECT_NAME}-{number}.phase
+  _base=$(basename "$_pf" .phase)
+  if [[ "$_base" =~ -session-${PROJECT_NAME}-([0-9]+)$ ]]; then
+    _issue_num="${BASH_REMATCH[1]}"
+  else
+    continue
+  fi
+  # Query Forge for issue/PR state
+  _issue_json=$(forge_api GET "/issues/${_issue_num}" 2>/dev/null || echo "")
+  [ -n "$_issue_json" ] || continue
+  _state=$(printf '%s' "$_issue_json" | jq -r '.state // empty' 2>/dev/null)
+  [ "$_state" = "closed" ] || continue
+  # Enforce 24h grace period after closure
+  _closed_at=$(printf '%s' "$_issue_json" | jq -r '.closed_at // empty' 2>/dev/null)
+  [ -n "$_closed_at" ] || continue
+  _closed_epoch=$(date -d "$_closed_at" +%s 2>/dev/null || echo 0)
+  _now=$(date +%s)
+  _elapsed=$(( _now - _closed_epoch ))
+  if [ "$_elapsed" -gt 86400 ]; then
+    rm -f "$_pf"
+    echo "  Cleaned: $(basename "$_pf") — issue #${_issue_num} closed at ${_closed_at}"
+    _cleaned_any=true
+  else
+    _remaining_h=$(( (86400 - _elapsed) / 3600 ))
+    echo "  Grace: $(basename "$_pf") — issue #${_issue_num} closed, ${_remaining_h}h remaining"
+  fi
+done
+if [ "$_cleaned_any" = false ]; then
+  echo "  None"
+fi
+echo ""
+
 # ── Lock Files ────────────────────────────────────────────────────────────
 
 echo "## Lock Files"