Phase 0 go-live polish: hands-off incremental sync + refresh action

- backend/ingest/sync_scheduler.py: periodic incremental-sync loop (every
  CRM_INGEST_SYNC_INTERVAL_MIN min); resilient, --once for testing.
- start9/0.4: "Refresh search index" action (incremental sync.py); entrypoint
  launches the scheduler as a background process when Spark/Qdrant are set;
  CRM_INGEST_SYNC_INTERVAL_MIN env; pre-release note on fastembed/mcp pins.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/ingest/sync_scheduler.py

@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+"""Hands-off periodic incremental-sync loop.
+
+Runs `sync.run()` every CRM_INGEST_SYNC_INTERVAL_MIN minutes so the Qdrant index
+tracks CRM changes without manual action. Mirrors the email-sync / backup
+scheduler pattern already used in this codebase. Resilient: a failed cycle is
+logged and the loop continues. Intended to be launched as a background process
+by the StartOS docker_entrypoint.sh (only when Spark/Qdrant are configured).
+
+    python3 backend/ingest/sync_scheduler.py --db /data/crm.db
+    python3 backend/ingest/sync_scheduler.py --db data/crm_dev.db --once   # one cycle (test)
+"""
+import argparse
+import os
+import sys
+import time
+import traceback
+
+import config
+import sync
+
+
+def _log(msg):
+    sys.stderr.write(f"[ingest-scheduler] {msg}\n")
+    sys.stderr.flush()
+
+
+def loop(db, interval_min, fuzzy):
+    interval = max(60, int(interval_min) * 60)
+    _log(f"started: every {interval_min} min on {db} (fuzzy={fuzzy})")
+    while True:
+        try:
+            s = sync.run(db, fuzzy=fuzzy)
+            _log(f"{s['mode']}: embedded {s['rows_embedded']} chunk(s); {s['qdrant_points']} points")
+        except Exception as exc:
+            _log(f"sync FAILED (continuing): {exc}\n{traceback.format_exc()}")
+        time.sleep(interval)
+
+
+def main():
+    ap = argparse.ArgumentParser()
+    ap.add_argument("--db", default=config.DEFAULT_DB)
+    ap.add_argument("--interval-min", type=int,
+                    default=int(os.environ.get("CRM_INGEST_SYNC_INTERVAL_MIN", "60")))
+    ap.add_argument("--fuzzy", action="store_true", help="also run the local-Qwen fuzzy tier each cycle")
+    ap.add_argument("--once", action="store_true", help="run a single cycle and exit (testing)")
+    args = ap.parse_args()
+    if args.once:
+        print(sync.run(args.db, fuzzy=args.fuzzy))
+        return
+    loop(args.db, args.interval_min, args.fuzzy)
+
+
+if __name__ == "__main__":
+    main()