Replace all Save buttons on the Settings page with debounced auto-save:
- useAutoSave hook: debounce with latest-payload-wins, flush() for blur,
pending-edit flush on unmount, status machine (idle/saving/saved/error)
with saved fading back to idle. Covered by 6 Vitest tests (fake timers).
- SaveStatus pill (framer-motion) in the page header and notification card
headers — Saving…/Saved/Save failed.
- Timing per control: toggles/selects/channel ~150-400ms; typed inputs
(email, URLs, grace period, drift pct) 900ms + flush on blur.
- Push token never auto-saves mid-type: saves on blur only, so a partial
token can never overwrite a working one.
- Notification cards no longer refetch parent settings on save (would
clobber in-flight edits under auto-save).
- Decision: no undo toast — settings are non-destructive and instantly
re-editable; undo would add noise without safety.
- vitest include now picks up .jsx tests; jsdom + @testing-library/react
added as devDependencies.
d9a441dff6