## What kind of change does this PR introduce?
Add `Markdown` component
- as a ui-pattern
- docs in design-system
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Introduced a Markdown UI pattern with full documentation and a docs
sidebar entry.
* Markdown component supports composable renderers, optional lazy syntax
highlighting, and customizable element overrides.
* Added many interactive examples (full demo, headings, paragraphs,
lists, links, inline code, blockquotes, code blocks, tables, images,
horizontal rules) plus Quote and Avatar demos.
* **Documentation**
* New MDX guide detailing usage, props, and customization previews.
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[](https://app.coderabbit.ai/change-stack/supabase/supabase/pull/46325?utm_source=github_walkthrough&utm_medium=github&utm_campaign=change_stack)
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## What kind of change does this PR introduce?
Bug fix
## What is the current behavior?
- Links on the UI Patterns introduction page are wrong and therefore 404
- Introduction pages on the sidebar are also wrong and 404
## What is the new behavior?
Fixes for both of the above
## Additional context
Thanks [Emilio](https://github.com/supabase/supabase/pull/42309) for
letting us know!
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Documentation**
* Updated navigation structure in the design system documentation to
direct users to introduction pages for UI Patterns, Fragments, and
Components sections.
* Refined internal documentation links for improved navigation
consistency.
<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
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Francesco Sansalvadore
