Add log/*.log to .gitignore and remove development.log

Update .gitignore to exclude all log files in the log/ directory
to prevent them from being tracked in the repository.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: takaokouji

.gitignore

@@ -19,6 +19,7 @@ test/version_tmp
 tmp
 coverage
 test/log
+log/*.log
 test_db
 test_db-journal
 .idea