iframe-scrapper

Use when modifying the iframe DOM mirror (server `sanitize.ts`) or the in-iframe overlay script (`frontend/src/lib/overlay.ts`). Covers the sanitization pipeline rules, the overlay script contract, the postMessage protocol, and the cross-package sync requirement.

Use when opening a pull request for this repository. Enforces atomic commits, the required PR body shape (quick explainer of what we're doing + why), and the mandatory assignee.

Use when adding or modifying a Fastify route in `server/src/routes/`. Covers the buildApp DI pattern, request validation with Fastify schemas, error mapping per `09-api-contracts.md`, and the matching test template.

Use when adding or modifying a Stimulus controller in `frontend/src/controllers/`. Covers naming, registration, targets/values/actions conventions, custom events, and the matching test template.

Use when writing or running tests in either package (frontend Stimulus/lib or server Fastify/sanitizer/Playwright). Provides Vitest setup, mounting helpers, route inject patterns, and Playwright stubbing templates.