515 tests across 38 files. Branch coverage 88%, function coverage 83%
on testable logic (stores, composables, api, utils, services, router).
New test files: websocket, useLoginSounds, useMobileBackButton,
useControllerNav, routes. Extended: rpc-client (99.5%), container store
(100%). Fixed: useNavSounds AudioContext mock, type errors across tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
