cleanup: remove dead code and duplicate docs

- Remove session-ses_2f27.md (161KB raw session log)
- Remove 49 ROOT_* duplicate files across REFERENCE/
- Remove 14 duplicate files between REFERENCE/ root and history/
- Remove asr_legacy.rs (dead code, replaced by asr.rs)
- Remove src/core/worker/ (duplicate JobWorker)
- Remove src/core/layers/ (empty directory)
- Remove 4 .bak files in src/
- Remove 7 dead private methods in worker/processor.rs
- Remove backup directory from git tracking

scripts/update_person_demographics.py

@@ -4,12 +4,8 @@ Update person demographics (Age, Gender) using InsightFace.
 This script scans the representative face of each person and updates the DB.
 """
 
-import os
 import cv2
-import json
 import psycopg2
-import numpy as np
-import insightface
 from insightface.app import FaceAnalysis
 
 # Configuration
@@ -114,9 +110,9 @@ def main():
                 # 6. Update
                 update_person_db(conn, person_id, age, gender)
             else:
-                print(f"  -> Face not found or attributes missing in this frame.")
+                print("  -> Face not found or attributes missing in this frame.")
         else:
-            print(f"  -> Failed to retrieve frame.")
+            print("  -> Failed to retrieve frame.")
 
     print("=== Done ===")
     conn.close()