feat: Add author's note cbs

[miladiashe]

PR Checklist

• Required Checks
  • Have you added type definitions?
  • Have you tested your changes?
  • Have you checked that it won't break any existing features?
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  • Have you checked if it works normally in all models?
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Summary

Add CBS for getting Author's note.

Related Issues

None

Changes

Add one cbs, {{authornote}}, for getting author's note slot.

Impact

None. only adding new feature

Additional Notes

I madt this CBS because I wanted to make author's note as user role, but I found it is impossible and there are no cbs to get author's note to custom

Footnotes

1. Modifies the behavior of prompting, requesting, or handling responses from AI models. ↩

2. Over 80% of the code is AI generated. ↩