Feature: Add Timed Rewards System (v1.3.0)

feat: v1.2.1 - Add permissions, config auto-update, and fix shutdown …

…data loss

- feat: Added permission checks for all commands (playtime.check, .top, .gui, .reload).
- feat: Added 'topStyle' setting to config to toggle between text or GUI for /playtime top.
- fix: Fixed data loss issue where online players were not saved during server shutdown.
- fix: Implemented username caching in SessionListener to prevent 'cannot find symbol' errors on quit.
- chore: Added setDefaults() to ConfigManager to automatically update config files without deletion.
- chore: Updated default resources/config.json with new settings and messages.

feat: add PlaytimeAPI for external plugin integration

- Created 'PlaytimeAPI' singleton class to expose service methods safely
- Added methods for retrieving Total/Daily/Weekly stats, Ranks, and Top Lists
- Added 'formatTime' utility for consistent time display across plugins
- API uses existing 'PlaytimeService' logic to ensure data consistency

feat: add leaderboard GUI and live stat tracking

- Implemented complete GUI system (Leaderboard) from scratch
- Added new UI resources (PlaytimeLeaderboard.ui, Entry.ui, textures)
- Added 'PlaytimeLeaderboardGui' class to handle UI logic
- Updated 'PlaytimeService' to include live session time in database queries
- Added 'GuiSettings' to config for full text customization
- Registered new '/playtime menu' command argument
- Bumped version to 1.1.0

Initial release v1.0.0