fix: resolve CI/CD linting issues

- Remove unused imports (F401) from analyzers and test files
- Remove unused typing imports (Any, Dict, List, Optional)
- Remove unused datetime imports
- Remove unused rich.columns import
- Remove unused pytest imports in test files

tests/test_models.py

@@ -1,4 +1,3 @@
-import pytest
 from datetime import datetime
 from src.models.data_structures import (
     Author,