feat: add role management and usage tracking modules

- Implemented role parsing and loading functionality in roles.js, allowing for structured role definitions with metadata.
- Added tests for role management to ensure correct parsing and loading of roles.
- Created usage.js to track API usage metrics, including token counts and rate limits.
- Developed tests for usage tracking to validate functionality and edge cases.
- Enhanced overall code structure and documentation for clarity and maintainability.

entrypoint.sh

@@ -1,11 +1,6 @@
 #!/bin/bash
+set -e
 
-echo "Gitea Server Url: $GITEA_SERVER_URL"
+echo "🚀 AI Code Review Action 啟動"
 
-echo "Gitea Repository: $GITEA_REPOSITORY"
-
-echo "Gitea Token: $GITEA_TOKEN"
-
-echo "Text: $TEXT"
-
-echo "text=$TEXT" >> "$GITHUB_OUTPUT"
+exec node /app/main.js