docs-core

The Rust docs pipeline core (ADR-0004 §2.5) — consolidating what Tachyon (16 crates), docs-pipeline, and the eight starlight-* plugins do in three languages, with the one seam the ecosystem has no answer for: astro-island-compatible island emission, so a Rust-rendered shell can hydrate the estate's existing SolidJS bundles (Leptos/Dioxus islands are Rust/WASM-only and cannot).

```island nav-search client=visible
{"count": 3}
```

renders to:

<docs-island component-url="/_assets/islands/nav-search.js" client="visible">
  <script type="application/json" data-island-props>{"count":3}</script>
</docs-island>

and islands/island.mjs (dependency-free, ~120 lines) hydrates it: props parsed with JSON.parse, each component URL imported at most once, load / visible / idle hints, docs:hydrated events.

M1 scope

• In: CommonMark+GFM → HTML (headings, paragraphs, emphasis/strong/ strike, inline + fenced code, links, images, lists incl. task lists, blockquotes, rules) and island fences. Raw HTML passes through (the mdBook/Zola/Starlight contract for first-party content); island props are validated Rust-side and JS-side, and < is escaped so a props payload can never terminate the script element.
• Wave 2 (deliberately absent, not silently): search indexing (adopt Pagefind), versioning, i18n, math (latex2mathml), diagrams (D2), sanitization for untrusted content (ammonia), dev server.

Tests

cargo test (10 tests + doctest, clippy -D warnings clean) and bun test islands/ (9 headless tests of the shim's pure half).

Licensed under MIT OR Apache-2.0.