[Lixxx1]

Summary

Fixes #24.

• Replace the basic Markdown renderer with GFM table support and KaTeX math rendering, including inline and display formulas.
• Keep wide tables and formulas horizontally scrollable within the sidebar, while preserving file links and external-link handling.
• Preserve complete math and fenced-code blocks during streaming; leave code literals, currency, and incomplete formulas as text.
• Bundle rendering scripts, styles, and fonts locally. Escape model-provided HTML, sanitize Markdown output, and keep KaTeX trust disabled without weakening the script CSP.
• Add rendering, security, streaming, and asset-loading regression tests.

This PR is based directly on main and is independent of the DSH 0.1.2 migration in #25. README files and the extension version are unchanged.

Validation

• Frozen-lockfile install passed.
• pnpm check passed: 36 test files, 196 tests passed and 1 skipped, plus type checking and both bundles.
• Browser preview checked in dark and light themes at a narrow sidebar width.
• VSIX file-list inspection confirmed bundled scripts, CSS, and local fonts.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-09T14:50:02.500836Z	18e3713	PR opened

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