feat: operational status endpoint + reconciler/peer state tracking 📊

- ReconciliationWorker._last_run stores per-pass stats (da_servers_polled,
  zones_in_da/db, orphans_found/queued, hostnames_backfilled/migrated,
  zones_healed, duration_seconds, dry_run flag)
- ReconciliationWorker.get_status() exposes state for API/UI consumption
- _heal_backends() now returns healed count
- PeerSyncWorker.get_peer_status() serialises _peer_health to JSON-safe dict
  (url, healthy, consecutive_failures, last_seen) with summary totals
- WorkerManager tracks dead-letter count; queue_status() now returns nested
  reconciler/peer_sync dicts replacing flat reconciler_alive/peer_syncer_alive
- New GET /status endpoint (StatusAPI) aggregates queue depths, worker liveness,
  reconciler last-run, peer health, and live zone count; computes ok/degraded/error
- .gitignore: exclude .claude/, .vscode/, .env (always local)
- app.yml: add documented datastore section (SQLite default + MySQL commented)
- 164 tests passing (23 new tests added)

tests/test_peer_sync.py

@@ -394,3 +394,53 @@ def test_sync_empty_peer_list(patch_connect, monkeypatch):
     monkeypatch.setattr("directdnsonly.app.peer_sync.requests.get", mock_get)
 
     worker._sync_from_peer(_make_peer())
+
+
+# ---------------------------------------------------------------------------
+# get_peer_status
+# ---------------------------------------------------------------------------
+
+
+def test_get_peer_status_no_contact_yet():
+    worker = PeerSyncWorker(BASE_CONFIG)
+    status = worker.get_peer_status()
+
+    assert status["enabled"] is True
+    assert status["total"] == 1
+    assert status["healthy"] == 1
+    assert status["degraded"] == 0
+    assert status["peers"][0]["url"] == "http://ddo-2:2222"
+    assert status["peers"][0]["healthy"] is True
+    assert status["peers"][0]["last_seen"] is None
+
+
+def test_get_peer_status_after_success():
+    worker = PeerSyncWorker(BASE_CONFIG)
+    worker._record_success("http://ddo-2:2222")
+    status = worker.get_peer_status()
+
+    assert status["healthy"] == 1
+    assert status["degraded"] == 0
+    assert status["peers"][0]["last_seen"] is not None
+
+
+def test_get_peer_status_after_degraded():
+    from directdnsonly.app.peer_sync import FAILURE_THRESHOLD
+
+    worker = PeerSyncWorker(BASE_CONFIG)
+    for _ in range(FAILURE_THRESHOLD):
+        worker._record_failure("http://ddo-2:2222", Exception("timeout"))
+
+    status = worker.get_peer_status()
+    assert status["healthy"] == 0
+    assert status["degraded"] == 1
+    assert status["peers"][0]["healthy"] is False
+
+
+def test_get_peer_status_disabled():
+    worker = PeerSyncWorker({})
+    status = worker.get_peer_status()
+
+    assert status["enabled"] is False
+    assert status["total"] == 0
+    assert status["peers"] == []