chore(dev): add tests directory to ruff format command

Include tests/ in the ruff format command to ensure consistent formatting
across test files.

Author: S1M0N38

.claude/settings.json

@@ -10,7 +10,7 @@
           },
           {
             "type": "command",
-            "command": "ruff format -s src/balatrobot"
+            "command": "ruff format -s src/balatrobot tests/"
           }
         ]
       }