refactor(settings): unify card headers, integration verbs, test buttons, and tap targets

Holistic consistency pass over the settings and integration surfaces so the
same concept reads and behaves the same way everywhere.

- Card headers: migrate the four integration cards (Withings, WHOOP,
  Fitbit/Google Health, Mood Log) plus the profile, passkeys, avatar, about,
  api-endpoints, api-tokens, and sharing cards onto the shared
  SettingsCardHeader primitive. Extend the primitive with an inline title
  accessory slot (Fitbit tag + experimental badge) and a multi-line
  description slot (overlap / experimental / deprecation sub-notes), keeping
  the rendered result identical.
- Integration verbs: normalise Mood Log onto the canonical "Sync now" /
  "Sync all data" / "Synchronize" set used by the other integrations, across
  all six locales. Swap the full-sync icon from Download to RefreshCw and
  align its action-row icon metrics with the sibling cards.
- Test buttons: migrate Telegram and ntfy off their hand-rolled "Test
  message" buttons onto the shared TestConnectionButton, so every channel and
  integration test control shares one icon, label, latency readout, and error
  taxonomy. Retire the now-unused testMessage / testSent strings.
- ntfy auth-token placeholder no longer reuses the "Saved" status string;
  it now reads "Saved — enter new to replace" like the other secret fields.
- Save-success copy: collapse the moodLog and Telegram bespoke strings onto
  the shared settings.saved string.
- Tap targets: floor every size="sm" action-row button (sync / full-sync /
  test / disconnect / save / connect-secret copy) at min-h-11, fixed at the
  TestConnectionButton source and across the cards, so they clear the 44px
  touch minimum.
- Contrast: the onboarding source-card badge moves from muted-on-muted to
  text-foreground; web-push card body rhythm aligns on space-y-4; Mood Log's
  deprecation note drops its bespoke 11px-italic treatment for the shared
  sub-note style.

(cherry picked from commit 11931d14b7875b7e2184a3b373d7a34b842f8eae)

src/components/onboarding/SourceCardGrid.tsx

@@ -227,7 +227,7 @@ function SourceCardItem({
         <h2 className="text-base font-semibold tracking-tight">{titleLabel}</h2>
         {badgeLabel ? (
           <span
-            className="bg-muted text-muted-foreground mt-1 inline-flex items-center rounded-full px-2 py-0.5 text-[10px] font-medium uppercase tracking-wide"
+            className="bg-muted text-foreground mt-1 inline-flex items-center rounded-full px-2 py-0.5 text-[10px] font-medium uppercase tracking-wide"
             data-testid={`source-badge-${card.slug}`}
           >
             {badgeLabel}