Final slice of the Welcome surface. Four steps that prove
the operator has the basic loop wired up; each step is
a live probe against the running hub, no manual ticks.
The four checked signals:
1. System AI configured
→ `HubService.systemAiStatus().enabled`
2. Public capability source added
→ `listMcpClients()` returns at least one entry
3. Text module installed
→ `listModules()` contains a name starting with `text.`
4. Saved flow run
→ any `flow.completed` event in the last 100 audit
events
All four probes fire in parallel from `_OnboardingChecklist`'s
`_refresh()`. Failures stay false (catchError) so a hub that
is briefly unreachable doesn't blank the whole row — the
operator hits the explicit Refresh icon to retry.
UX:
- Renders between hero and pillars so the actionable path
beats the educational content for screen real estate.
- Each row: status icon (○ pending / ✓ done) + title +
one-line hint pointing the operator at the right Studio
surface + status pill.
- Done rows strike-through the title and dim it; pending
rows stay full-strength.
- When all four flip to done, an "All four steps complete"
footer appears with a `Hide checklist` button. Clicking
persists `welcome.checklist.dismissed = true` via
SharedPreferences; the section is gone for good (we don't
re-nag operators who chose a non-default path).
15 new ARB keys for the section header, body, four rows
plus done/pending pills, all-done footer, dismiss /
refresh / refreshing button labels.
Three-phase plan from `docs/landing-page-design.md` is now
fully shipped: Phase A scaffolding (v0.37.0), Phase B
embedded doc reader (v0.38.0), Phase C live checklist
(v0.39.0).
Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>