Enhance project structure and add new files for enrichment and analysis

- Updated AGENTS.md to reflect changes in CLI commands and module organization, including the addition of an enrichment step and new functional modules.
- Introduced analysis.json, identities.json, inventory.csv, and plan.json to support enriched metadata and execution planning.
- Added CODE_IMPROVEMENTS.md to document identified code issues and proposed solutions for future enhancements.
- Updated README.md to include new enrichment features and configuration options.
- Removed unused dependency on ffmpeg-python from pyproject.toml.

These changes improve the overall functionality and maintainability of the Video Library Manager project.

tests/test_state.py

@@ -2,7 +2,7 @@
 
 import json
 import pytest
-from datetime import datetime
+from datetime import datetime, timezone
 from pathlib import Path
 from vlm.state import (
     load_state,
@@ -33,7 +33,8 @@ class TestLoadSaveState:
         
         assert loaded.states == {}
         assert loaded.version == '1.0'
-        assert loaded.last_updated == datetime(2024, 1, 1, 12, 0, 0)
+        # load_state normalizes naive ISO timestamps to UTC
+        assert loaded.last_updated == datetime(2024, 1, 1, 12, 0, 0, tzinfo=timezone.utc)
     
     def test_save_and_load_with_states(self, tmp_path):
         """Test saving and loading state store with file states."""
@@ -74,13 +75,14 @@ class TestLoadSaveState:
         assert state1.file_path == file1
         assert state1.status == "reviewed"
         assert state1.reason == "Checked manually"
-        assert state1.updated_at == datetime(2024, 1, 1, 12, 0, 0)
+        # load_state normalizes naive ISO timestamps to UTC
+        assert state1.updated_at == datetime(2024, 1, 1, 12, 0, 0, tzinfo=timezone.utc)
         
         state2 = loaded.states[str(file2)]
         assert state2.file_path == file2
         assert state2.status == "ignored"
         assert state2.reason is None
-        assert state2.updated_at == datetime(2024, 1, 2, 12, 0, 0)
+        assert state2.updated_at == datetime(2024, 1, 2, 12, 0, 0, tzinfo=timezone.utc)
     
     def test_save_creates_parent_directory(self, tmp_path):
         """Test that save_state creates parent directories if needed."""