[codex] Set up monorepo foundation

[jderochervlk]

Context

This is the foundation PR for splitting the existing docs site into a monorepo before adding the separate interactive guide site. It keeps the current docs app behavior intact while moving it under apps/docs and making root scripts delegate to the docs workspace.

The branch has been refreshed onto current master as a single commit.

Summary

• Add a Yarn workspace root with apps/* and packages/*, and move the existing site package to apps/docs as @rescript-lang/docs.
• Move the docs app, source, content, scripts, tests, assets, functions, and config files under apps/docs with mostly pure renames.
• Update root scripts, Makefile, ignore/format config, generated-script paths, source/edit links, and deployment workflows for the new docs workspace location.
• Carry the latest master docs/content/test updates into the apps/docs layout, including the 2026 retreat recap assets, new partner/logo assets, and landing-page snapshot coverage.
• Keep this PR limited to monorepo structure; it does not add guide content or a guide app yet.

Validation

• yarn install --immutable
• yarn build:res
• yarn ci:format
• yarn build:scripts
• yarn build:update-index
• yarn workspace @rescript-lang/docs ci:format
• yarn build
• git diff --check origin/master...HEAD

Known test caveat

timeout 180s yarn test timed out while testing examples in apps/docs/markdown-pages/docs/manual/array-and-list.mdx. The full yarn test still does not complete in this checkout. This appears separate from the monorepo production build path, which exits 0.

[github-actions]

Cloudflare deployment

Deployement ID: ea97cfd5-43f4-46a5-a712-cfd96be03b05
Deployment Environment: preview

⛅️ wrangler 4.63.0 (update available 4.86.0)
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✨ Deployment alias URL: https://vlk-monorepo-foundation.rescript-lang.pages.dev

[chatgpt-codex-connector]

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