## Summary
- `cheerio` pulls `encoding-sniffer` → `whatwg-encoding@3.1.1` (deprecated), causing a warning on every `npm install -g hyperframes`
- `linkedom` was already bundled into the CLI via tsup `noExternal` and has zero deprecated transitive deps
- Rewrote `htmlBundler.ts` and `subComposition.ts` to use standard DOM APIs via `linkedom`
- Added a `parseHTMLContent` helper that wraps HTML fragments in a full document structure (required for `linkedom` to populate `document.body`)
- Removed `cheerio` from `cli` dependencies and tsup `external` list
- Replaced `cheerio` with `linkedom` in `core` `optionalDependencies`
## Test plan
- [x] All 411 tests pass (`bun run test` in `packages/core`)
- [x] Full monorepo build succeeds (`bun run build`)
- [x] TypeScript typecheck passes
## Summary
- rewrite CSS `url(...)` asset paths from sub-compositions before styles are hoisted into bundled/master preview output
- rewrite standalone sub-composition preview HTML so `src`/`href` paths keep resolving correctly under the preview root `<base>`
- add regression tests for bundled CSS asset rewriting and standalone sub-composition preview rewriting
## Root cause
Standalone composition previews reused the project `<head>` with a preview-root `<base href="/api/projects/:id/preview/">`, but the sub-composition body still contained `../...` asset references. Those escaped the preview route and 404ed. Separately, bundled preview already rewrote `<img src="../...">` paths but left hoisted CSS asset references like `@font-face src: url("../font.woff2")` untouched.
## Validation
- `pnpm --filter @hyperframes/core exec vitest run src/compiler/htmlBundler.test.ts src/studio-api/helpers/subComposition.test.ts`
- `pnpm --filter @hyperframes/core exec tsc --noEmit`
- `pnpm --filter @hyperframes/producer exec tsc --noEmit` *(blocked by pre-existing `packages/producer/src/services/deterministicFonts.ts` importing missing generated file `./fontData.generated.js` in the worktree install)*
- browser verification with `agent-browser` against the local preview server using `/Users/miguel07code/dev/test-hyperframes/heygen-promo`
## Browser proof
Verified the fixed preview routes in-browser after seeking to visible frames:
- standalone composition preview
- bundled master preview
## Summary
Extracts all studio API routes into a shared Hono-based module at `@hyperframes/core/studio-api`.
### Architecture
- **`StudioApiAdapter` interface** — consumers inject host-specific behavior (project resolution, bundling, rendering, thumbnails)
- **Shared route modules**: projects, files, preview, lint, render, thumbnail
- **Shared helpers**: `isSafePath`, `walkDir`, `getMimeType`, `buildSubCompositionHtml`
### What this PR does
- Creates the shared module with all API routes extracted from both `vite.config.ts` and `studioServer.ts`
- Both consumers will be refactored in follow-up commits to mount this module with their own adapter
### What stays in each consumer
- **Vite**: SSR module loading, Puppeteer thumbnails, file watcher + HMR, producer HTTP proxy, multi-project scanning
- **CLI**: in-process `executeRenderJob`, local runtime serving, browser management, SPA static file serving
### Follow-up needed
- [ ] Refactor `packages/studio/vite.config.ts` to use `createStudioApi(adapter)` via `@hono/node-server`'s `getRequestListener`
- [ ] Refactor `packages/cli/src/server/studioServer.ts` to use `createStudioApi(adapter)`
- [ ] Add `./studio-api` export path to `packages/core/package.json`
- [ ] Add `hono` as peer dependency of `@hyperframes/core`
## Test plan
- [ ] Verify shared module compiles without type errors
- [ ] After consumer refactoring: all studio features work identically via both vite dev and CLI embedded servers
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Miguel Ángel