Summary

This PR improves markdown-to-Google-Docs fidelity used by appendMarkdownToGoogleDoc and replaceDocumentWithMarkdown by adding support for patterns that previously degraded formatting.

What Changed

• Add inline-code styling (monospace + code-like colors).
• Add fenced/code-block rendering and code styling.
• Preserve nested list levels via leading-tab indentation.
• Convert markdown task lists ([x] / [ ]) to Google Docs checkbox bullets.
• Prevent list bullet ranges from bleeding into following headings.
• Apply list bullet requests bottom-up to avoid index-shift failures.
• Add regression tests for the above behavior.

Validation

• Ran: node --test tests/markdown.test.js
• Result: 22 passed, 0 failed.

Before / After Evidence (Public-Safe Fixture)

Used a synthetic markdown fixture (no internal content).

• Before (origin/main converter):
  • checkbox bullets: not generated
  • monospace code style requests: 0

• After (this branch):
  • checkbox bullets: generated
  • monospace code style requests: 3