refactor CLI command modules and synchronize docs

tests/test_cli_rollback.py

@@ -2,7 +2,7 @@
 
 import json
 from pathlib import Path
-from datetime import datetime
+from datetime import datetime, timezone
 
 import pytest
 from click.testing import CliRunner
@@ -46,7 +46,7 @@ def sample_rollback_log(tmp_path):
             ),
             success=True,
             error_message=None,
-            executed_at=datetime.now()
+            executed_at=datetime.now(timezone.utc)
         ),
         OperationResult(
             operation=FileOperation(
@@ -59,14 +59,14 @@ def sample_rollback_log(tmp_path):
             ),
             success=True,
             error_message=None,
-            executed_at=datetime.now()
+            executed_at=datetime.now(timezone.utc)
         )
     ]
     
     rollback_log = RollbackLog(
         log_id="test-log-id",
         execution_plan_id="test-plan-id",
-        executed_at=datetime.now(),
+        executed_at=datetime.now(timezone.utc),
         operations=operations
     )