Unify analysis pipeline around the TSV; move tracked DBs out of cloud sync

- Tracked DBs now live at /mnt/data/projects/cupido/tracked/ (out of
  ownCloud to avoid sync conflicts and bandwidth churn). config.py
  TRACKING_OUTPUT_DIR points there; the docker-compose for ethoscope-lab
  mounts it world-readable for JupyterHub users.
- New scripts/export_video_db_index.py joins all_video_info_merged.xlsx
  with the video inventory and the on-disk DBs, producing a TSV that has
  one row per fly/ROI plus training/testing video and DB paths. Handles
  approximate xlsx times, cross-day training/testing, the 12 AM/PM
  ambiguity, and date typos.
- scripts/load_roi_data.py rewritten as a TSV-driven loader returning a
  single DataFrame with session and metadata columns. calculate_distances
  and the two flies_analysis notebooks migrated to use it; downstream
  trained/naive splits remain available via simple equality filters.
- Metadata vocabulary canonicalized: {naïve, niave, untrained, test} all
  resolve to {trained, naive}. Normalization happens at the TSV-export
  boundary (idempotent); the xlsx and the 2025-07-15 legacy CSV were
  edited in place to remove the worst variants.
- scripts/monitor_tracking.py rate calculation fixed: with N parallel
  workers, completions arrive in bursts; the old formula divided by burst
  width and reported nonsense rates. Now uses a 6 h window denominator.
- scripts/track_videos.py: BGRMovieCamera retries cv2.read on transient
  NFS hiccups and a post-tracking completeness gate (≥ 90 % of expected
  duration via MAX(t) across all 6 ROIs) deletes silent partial DBs.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

scripts/config.py

@@ -13,5 +13,8 @@ VIDEOS_ROOT = Path("/mnt/ethoscope_data/videos")
 VIDEO_INFO_XLSX = PROJECT_ROOT.parent / "all_video_info_merged.xlsx"
 INVENTORY_CSV = DATA_METADATA / "video_inventory.csv"
 TARGETS_DIR = PROJECT_ROOT / "data" / "targets"
-TRACKING_OUTPUT_DIR = PROJECT_ROOT / "data" / "tracked"
+# Reason: tracking DBs are large binary files that don't belong in
+# ownCloud-synced storage (sync conflicts + bandwidth). They live on the
+# local data volume instead. Regenerable from videos + target JSONs.
+TRACKING_OUTPUT_DIR = Path("/mnt/data/projects/cupido/tracked")
 LOGS_DIR = PROJECT_ROOT / "data" / "logs"