Add custom remark2rehype handlers

[ShadiestGoat]

Fixes #260

As a note - this looks like it adds a new dep mdast-util-to-hast. However, this actually just moves it out of the dependency of another pkg.

[changeset-bot]

🦋 Changeset detected

Latest commit: b9c6268

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
svelte-exmarkdown	Minor

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[ShadiestGoat]

@ssssota hmm.. is it up to me to add changesets in this PR? I can do it if needed

[ssssota]

Thanks for your contribution!

[codecov-commenter]

Codecov Report

❌ Patch coverage is 45.45455% with 18 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.14%. Comparing base (471ba46) to head (b9c6268).
⚠️ Report is 147 commits behind head on main.

Files with missing lines	Patch %	Lines
src/lib/utils.ts	45.45%	18 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #261      +/-   ##
==========================================
- Coverage   97.32%   92.14%   -5.18%     
==========================================
  Files           8        8              
  Lines         299      331      +32     
  Branches       46       30      -16     
==========================================
+ Hits          291      305      +14     
- Misses          8       26      +18     

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[ssssota]

@ShadiestGoat Please run pnpm fmt to format code.

[ShadiestGoat]

Hey @ssssota sorry for the long wait, I ran the formatter