Verified locally this time rather than in CI. The ci-tauri image is already on this machine, so `cargo fmt --check` can run in a throwaway container against the exact toolchain CI uses — no test run, no build, no local stack, just the formatter. Four consecutive pushes had failed on formatting alone; that class of failure is now catchable before it costs a cycle. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01SreJkbxB4gx8pPsu8QbLPi