fix: face group name read consistency, sync_file_status fix, cleanup ghost records, identity_agent replaced with face_dedup

- get_face_groups_handler: COALESCE(tp.name, tn.label) for name consistency
- sync_file_status: compare JSON vs pre_chunks (not chunk table)
- face consistency: compare frames.len() not total_faces
- cleanup 2 ghost records with NULL file_name/file_path
- replace identity_agent with face_dedup in pipeline stages
- remove identity_agent_api.rs and all references
- update required_processors to match actual processors
- update AGENTS.md with team responsibilities
- add Studio pipeline changes documentation

scripts/fix_stale_processing.sql

@@ -0,0 +1,22 @@
+-- Fix stale_processing files: status='processing' but job_id IS NULL
+-- These files should be reset to 'pending' so they can be processed properly
+
+-- Show current state
+SELECT file_uuid, file_name, status, job_id 
+FROM videos 
+WHERE status = 'processing' AND job_id IS NULL;
+
+-- Fix: Reset to pending
+UPDATE videos 
+SET status = 'pending', processing_status = NULL 
+WHERE status = 'processing' AND job_id IS NULL;
+
+-- Verify fix
+SELECT file_uuid, file_name, status, job_id 
+FROM videos 
+WHERE file_uuid IN (
+  '5e207a246fd6a2a65ee0a267440465ee',
+  '9cbeb112fcc5452e869755a539478061',
+  'bfba056f5021e2404b0870cc0b1fa851',
+  '2d0ec3a72d5dda98b10b3eb777650846'
+);