feat(docs): initialize fumadocs

[mezotv]

Adds fumadocs and a simple example page.

Note: Not happy with the navbar might need to cook a better one in the future! (Maybe copy the wouldyoubot.gg one)

[Copilot]

Pull Request Overview

This PR initializes Fumadocs, a documentation framework, for the Discord Components project. It sets up a complete documentation site with MDX support, automatic sitemap generation, and OpenGraph image generation.

• Adds Fumadocs dependencies and configuration for MDX-based documentation
• Creates initial documentation structure with example content and routing
• Implements SEO features including sitemap generation and OG image creation

Reviewed Changes

Copilot reviewed 19 out of 22 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
source.config.ts	Configuration for Fumadocs MDX processing with docs and meta schemas
package.json	Added Fumadocs dependencies and postinstall script
next.config.ts	Integrated MDX processing with Fumadocs
mdx-components.tsx	Configured MDX components for enhanced documentation features
lib/source.ts	Source loader configuration for documentation pages
content/docs/index.mdx	Initial documentation page with basic content
app/sitemap.ts	Dynamic sitemap generation including documentation pages
app/og/[...slug]/	OpenGraph image generation for documentation pages
app/layout.tsx	Updated root layout with Fumadocs provider and enhanced metadata
app/layout.config.tsx	Shared layout configuration for documentation
app/globals.css	Added Fumadocs styling and custom CSS variables
app/docs/	Documentation layout and dynamic page routing
app/api/search/route.ts	Search API endpoint for documentation
app/(home)/	Updated home page layout and styling
.source/	Generated files from Fumadocs build process

[tobias-hay]

LGTM