chore(lint): apply ruff --fix (4443 auto-fixes)

Auto-fixed categories:
- F401: unused imports removed
- I001: import blocks sorted
- W293: trailing whitespace stripped
- UP035: deprecated typing imports replaced
- SIM: simplify suggestions applied
- ARG: unused args prefixed with underscore
- T201: print statements removed
- F841: unused variables removed
- RUF059: unpacked variables prefixed

Remaining ~1500 unfixable errors (C901, B904, N806, E402) require manual work.

Backend smoke tests: 13/13 passed.

backend/src/scripts/create_admin.py

@@ -8,18 +8,18 @@
 #
 # @INVARIANT: Admin user must have the "Admin" role.
 
-import sys
 import argparse
+import sys
 from pathlib import Path
 
 # Add src to path
 sys.path.append(str(Path(__file__).parent.parent.parent))
 
-from src.core.database import AuthSessionLocal, init_db
 from src.core.auth.security import get_password_hash
-from src.models.auth import User, Role
-from src.core.logger import logger, belief_scope
 from src.core.cot_logger import seed_trace_id
+from src.core.database import AuthSessionLocal, init_db
+from src.core.logger import belief_scope, logger
+from src.models.auth import Role, User
 
 
 # #region create_admin [TYPE Function]