Guild Plugin

Fully adapted for Folia while maintaining compatibility with major plugin platforms. Fixed how timestamps are stored in the database.

The author needs to return to focus on studies for now. Due to limited availability, I may not be able to respond to issues or messages on other platforms promptly. There will also be no further plugin updates in the short term. If urgent modifications are needed, please feel free to adjust the source code directly. The latest code has been pushed to GitHub.