feat: add application command flag

[spifory]

Summary

This pull request adds the new APPLICATION_COMMAND_BADGE flag that was documented on https://github.com/discord/discord-api-docs/pull/5222.

Checklist

• [ ] If code changes were made, then they have been tested
  • [ ] I have updated the documentation to reflect the changes
  • [ ] I have formatted the code properly by running task lint
  • [ ] I have type-checked the code by running task pyright
• [ ] This PR fixes an issue
• [x] This PR adds something new (e.g. new method or parameters)
• [ ] This PR is a breaking change (e.g. methods or parameters removed/renamed)
• [ ] This PR is not a code change (e.g. documentation, README, ...)