Typecheck broken on main: AppNav.test.tsx missing jest-dom matcher types #25

What

pnpm typecheck (and therefore pnpm verify) fails on main with the following errors in apps/web/src/components/AppNav.test.tsx:

src/components/AppNav.test.tsx(18,45): error TS2339: Property 'toBeInTheDocument' does not exist on type 'Assertion<any>'.
src/components/AppNav.test.tsx(24,20): error TS2339: Property 'toHaveAttribute' does not exist on type 'Assertion<any>'.
... (9 total)

Why it happens

apps/web/src/test/setup.ts imports @testing-library/jest-dom which extends matchers at runtime, but apps/web/tsconfig.json has "types": ["vite/client"] and never pulls in the jest-dom type augmentations, so vitest's Assertion interface is unaware of toBeInTheDocument / toHaveAttribute.

Introduced by PR #24 (commit 5dea359 feat(green): AppNav left-sidebar navigation) — the runtime setup was added, the type bridge was not.

Reproduction

git checkout main
pnpm typecheck

Fails immediately in @medbridge/web typecheck.

Proposed failing test

There is no code-level test to add — pnpm typecheck is the test, and it is red on main today. The fix is verified when pnpm typecheck exits 0.

Proposed fix

Add "@testing-library/jest-dom" to apps/web/tsconfig.json's types array (or import '@testing-library/jest-dom/vitest' in src/test/setup.ts so the augmentation registers under vitest's Assertion). Either way, ensure @testing-library/jest-dom is a devDependency of apps/web.

Why this matters now

The agent loop runs pnpm verify before every commit. With main failing typecheck, new feature work cannot satisfy the gate cleanly. Filed from issue #19's iteration; #19's PR will note that verify cannot pass cleanly until this is resolved on main.