Provide users with help about what configuration options are available

[ttebify]

This pull request adds a new feature to the !config command to provide users with help about what configuration options are available.

The changes are made in src/handlers/ai-config.ts to add a new condition to the handleMessageAIConfig function. This condition checks for the user entering !config help and, if true, prints out a list of the possible configuration options.

The list of possible configuration options is generated by looping through the aiConfigTarget, aiConfigTypes, and aiConfigValues objects and collecting the keys of each. This list is then printed out as a message for the user.

The changes were made following the existing coding style and conventions of the project, and were tested to ensure that the functionality works as expected.

[navopw]

I will merge it later, thanks! 🚀