test: add unit, API, component and end-to-end test suites

The repo had no automated tests. Every change was verified by hand.

Adds four layers, 2023 tests in total, runnable with one command:

- 1191 unit tests over the pure logic in lib/, including the full
  computeProjectAccess permission matrix and the billing gate
- 167 component and hook tests in jsdom, covering the hooks that hold
  real logic rather than presentational wrappers
- 647 API integration tests against a real Postgres, with only auth()
  mocked, including a data-driven sweep asserting that none of the 60
  route modules answers 2xx to an unauthenticated caller
- 18 Playwright specs driving a real browser against a real build

Infrastructure: vitest.config.ts with three projects, a disposable
Postgres and MinIO in docker-compose.test.yml, factories and helpers
under tests/, scripts/test.sh as the single entry point, a pre-push
hook running bun run verify, and CI split into check, test and e2e jobs.

The test database is built with prisma db push plus a replay of the
hand-written SQL, because prisma migrate deploy cannot build this schema
from empty: the migration history has no captured baseline. This mirrors
what scripts/docker-db-bootstrap.ts already does in production, and
tests/setup/db-global.ts carries a drift guard so a new migration fails
the run until someone reviews it.

Production code is unchanged apart from one pure-function extraction out
of use-video-player.ts, which was too large to test in jsdom.

Several tests pin behaviour that looks wrong, each marked KNOWN BUG in
place. TESTING.md section 12 records where the plan turned out to be
wrong, and AGENTS.md now states which layer a change needs a test in.

tests/setup/component.ts

@@ -0,0 +1,95 @@
+// Per-file setup for the `component` Vitest project (jsdom environment).
+//
+// Two jobs:
+//   1. Register the jest-dom matchers (`toBeVisible`, `toHaveAccessibleName`, ...).
+//   2. Polyfill the browser APIs jsdom does not implement. Radix and the video
+//      player reach for these on mount, so without them a render throws before
+//      any assertion runs.
+import { afterEach } from 'vitest';
+import { cleanup } from '@testing-library/react';
+import '@testing-library/jest-dom/vitest';
+
+/**
+ * Testing Library normally registers this itself, but only when it can see a
+ * global `afterEach`. This repo runs Vitest without globals (every test file
+ * imports what it needs), so the auto-cleanup never installs and each rendered
+ * component stays mounted for the rest of the file: its effects keep running,
+ * its window/document listeners keep firing and the next test sees them. Do it
+ * explicitly here instead of in every test file.
+ */
+afterEach(() => {
+  cleanup();
+});
+
+/**
+ * jsdom has no CSS media query engine, so `window.matchMedia` is missing
+ * entirely. Every query reports as not matching, which keeps components on
+ * their desktop / no-preference code path.
+ */
+function createMediaQueryList(query: string): MediaQueryList {
+  return {
+    matches: false,
+    media: query,
+    onchange: null,
+    // Deprecated aliases, still used by some libraries.
+    addListener: () => {},
+    removeListener: () => {},
+    addEventListener: () => {},
+    removeEventListener: () => {},
+    dispatchEvent: () => false,
+  };
+}
+
+window.matchMedia = (query: string): MediaQueryList => createMediaQueryList(query);
+
+/**
+ * jsdom implements no layout, so it ships no `scrollIntoView`. Radix calls it
+ * when it moves focus inside a scrollable list.
+ */
+Element.prototype.scrollIntoView = () => {};
+
+/**
+ * jsdom does not implement ResizeObserver. A stub that never fires is enough:
+ * components only need the constructor not to throw, and any size-dependent
+ * behaviour belongs in E2E anyway.
+ */
+class ResizeObserverStub implements ResizeObserver {
+  observe(): void {}
+  unobserve(): void {}
+  disconnect(): void {}
+}
+
+globalThis.ResizeObserver = ResizeObserverStub;
+
+/**
+ * Pointer capture is unimplemented in jsdom. Radix uses it for its
+ * drag-to-select behaviour (Select, Slider, Menu) and throws without it.
+ */
+Element.prototype.hasPointerCapture = () => false;
+Element.prototype.setPointerCapture = () => {};
+Element.prototype.releasePointerCapture = () => {};
+
+/**
+ * jsdom raises "Not implemented" for media playback. Resolve instead, so the
+ * player hooks can await `play()`.
+ */
+HTMLMediaElement.prototype.play = () => Promise.resolve();
+HTMLMediaElement.prototype.pause = () => {};
+
+/**
+ * Object URLs are used by the upload previews. jsdom leaves both of these
+ * undefined.
+ */
+URL.createObjectURL = () => 'blob:openframe-test';
+URL.revokeObjectURL = () => {};
+
+/**
+ * jsdom does not implement `navigator.sendBeacon`. The watch-progress hook
+ * feature-detects it and silently skips its unload flush when it is missing, so
+ * without this stub that whole branch would be untestable. Tests spy on it.
+ */
+Object.defineProperty(navigator, 'sendBeacon', {
+  configurable: true,
+  writable: true,
+  value: () => true,
+});