Write tests, raise coverage

The test-writer agent does this end to end; this is its procedure, for doing it by hand or checking its work. .claude/rules/tests.md has which kind of test goes where.

1. Measure. bun run --filter @repo/<name> coverage for one package (unit and integration together, so the full Docker profile must fit), or bun run test:coverage for all of them; bun run --cwd apps/ai coverage for Python, bun run --filter @repo/mobile coverage for mobile. They take minutes: run them in the background. Note every uncovered line and branch.
2. Pick the kind for each gap:
   • pure logic: a unit test next to the file (src/<file>.test.ts);
   • anything touching Postgres, Valkey, email, auth, queues or HTTP: an integration test in the package's test/ (apps name them *.integration.test.ts), against the real service, as the service's own role, data from factories(db) in @repo/db/testing. In apps/api, test/harness.ts (startApi(<redis db>), createSession);
   • a user flow: a Playwright spec in apps/web/e2e/ or apps/mobile/e2e/;
   • a component: a story with a play function in packages/ui.
3. Write them. Error branches too: the typed AppError codes, the early returns, another organization seeing nothing. Third parties through the local fakes, never vi.mock of Prisma, Redis, BullMQ or a provider. No fixed sleeps: wait for the condition. No .skip, .only or coverage pragma (the edit hook refuses them).
4. Can't be tested automatically? Write the test anyway, skipped with the reason (it.skipIf(!process.env.<CREDENTIAL>)), and add a row to "Not tested automatically" in docs/testing.md saying why and how to run it by hand.
5. Reach 100%. bun run test:coverage merges every suite and names each file below 100%, with the lines, branches and functions no test reaches. A shared package counts what its callers' tests reach too. A line that truly can't be tested is either deleted or listed, with the reason, in "Coverage exceptions" in docs/testing.md.

Done when

• The new tests pass on their own and in the package's suite.
• Every file you touched is at 100% in bun run test:coverage.
• bun run lint, bun run check-types pass; the verify skill for anything that ran integration tests.