feat(frontend): ntfy.sh settings block in SettingsPanel

Adds a 'Notifications (ntfy.sh)' section below 'Backend URL' with:
- Enable toggle (master switch)
- Topic URL field (with security hint: anyone with the URL can read)
- Optional auth token (password input; placeholder reflects whether one
  is already stored, and a 'Clear stored token' button surfaces only when
  hasAuthToken=true)
- Per-event-type checkboxes driven by the eventTypes catalog returned
  from GET /notifications (so adding a new event type in core doesn't
  require a frontend change)
- Save + Send test buttons, with inline success/error feedback

The component hand-mirrors the NtfyConfig shape rather than importing it
from @dispatch/core — matching the existing pattern (lib/types.ts mirrors
a few core types) to keep node-only barrels out of the browser bundle.

0 files changed, 0 insertions, 0 deletions