Diagnostics were invisible in a packaged build: main catches did a bare
console.error (DevTools suppressed in prod, M31) and the renderer's logError
(M29) wrote to an unreachable console. Add a small leveled logger
(src/main/logger.ts) appending to <userData>/logs/aerofetch.log with size-capped
rotation; all app/fs access is lazy+guarded so it's a safe no-op under tests.
- Route the 5 main-process console.* catch sites (jsonStore write-fail, settings
write-fail + plaintext-secret warn, cookie loadURL, yt-dlp auto-update)
through the logger.
- Add a fire-and-forget log:write IPC channel + preload logError() so the
renderer's logError forwards failures to the main file sink (closes the M29
"sink" half the code comments deferred to CC8). mockApi + Api type updated.
- Unit-test pure formatLine/composeMessage + no-op safety; update the R6
jsonStore test to assert against the logger.
The user-facing toast half of CC8 ties to the global status surface (UI25/UX9).
typecheck + 258 tests + lint + prettier green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>