fix(insights): keep the assessment card polling while a stale text revalidates

The stale-while-revalidate path serves the last-good assessment on a cache
miss and returns a terminal payload, so the status hook stopped polling. The
worker warmed a fresh assessment out of band seconds later, but the open card
never picked it up — the stale text stuck until the page remounted.

Add a `revalidating` flag to the read-only miss outcome, set only when
last-good text is served AND a refresh was enqueued (false on the
suppressed-stub branch and when no prior text exists). Thread it through the
generic metric-status generator and the seven specialised generators onto the
wire, type it on the client, and make `nextStatusPollInterval` keep polling on
`preparing || revalidating`. The existing 12-attempt ceiling bounds both
signals, so a persistently failing generation still cannot poll forever.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
(cherry picked from commit c9217534fbdb304c4df1b6eb55fb19e4360b8a10)

src/app/insights/medications/page.tsx

@@ -63,6 +63,9 @@ interface MedicationComplianceStatusData {
   // cache miss while the worker warms the assessment; the card polls until
   // it lands. See `use-insight-status.ts` for the shared rationale.
   preparing?: boolean;
+  // v1.9.0 — last-good narrative served while a refresh is in flight; the
+  // card keeps polling (bounded) so the open page upgrades in-session.
+  revalidating?: boolean;
 }
 
 // v1.8.3 — client ceiling on the round-trip, mirroring the shared
@@ -129,6 +132,7 @@ export default function InsightsMedikamentePage() {
       nextStatusPollInterval(
         query.state.data?.preparing,
         query.state.dataUpdateCount,
+        query.state.data?.revalidating,
       ),
   });