feat: Encode dictionary schemas

[paleolimbot]

This PR adds support in the IPC writer for dictionary schemas, verifying support by removing skips and adding cases for all the valid dictionary index types in the parameterized test cases.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 64.61538% with 23 lines in your changes missing coverage. Please review.
✅ Project coverage is 79.21%. Comparing base (f11d517) to head (664ed3f).
⚠️ Report is 44 commits behind head on main.

Files with missing lines	Patch %	Lines
src/nanoarrow/ipc/encoder.c	64.61%	9 Missing and 14 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #882      +/-   ##
==========================================
- Coverage   79.96%   79.21%   -0.76%     
==========================================
  Files         105      106       +1     
  Lines       15461    15995     +534     
  Branches     1738     1861     +123     
==========================================
+ Hits        12364    12670     +306     
- Misses       1998     2156     +158     
- Partials     1099     1169      +70     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.