feat: running timers, symptom log, search, PDF export

- dashboard: ActiveTimers widget — live h:mm:ss for any in-progress timed event (breastfeed, nap, sleep, walk…), Terminer button patches endedAt
- dashboard: reorganised quick-log groups; Santé group (Température, Traitement, Symptôme)
- events: SYMPTOM type — tag chips (Fièvre, Reflux, Colique, Éruption, Toux, Congestion, Diarrhée, Vomissement, Irritabilité, Pleurs excessifs), stored in metadata.tags
- prisma: migration adding SYMPTOM to EventType enum
- search: GET /api/search (events by notes ILIKE, journal by content ILIKE), /search page with debounced input + keyword highlight
- nav: Recherche link added to LINKS + More drawer
- growth: PDF export button — generates formatted table with all measurements, zebra rows, downloads croissance-{name}.pdf

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/(app)/timeline/page.tsx

@@ -57,6 +57,10 @@ function getEventSummary(event: Event): string {
   if (event.type === "DIAPER_STOOL") return String(meta.color ?? "");
   if (event.type === "TEMPERATURE") return meta.value ? `${meta.value}°${meta.unit ?? "C"}` : "";
   if (event.type === "MEDICATION") return String(meta.name ?? "");
+  if (event.type === "SYMPTOM") {
+    const tags = (meta.tags as string[] | undefined) ?? [];
+    return tags.length > 0 ? tags.join(", ") : "";
+  }
   if ((event.type === "NAP" || event.type === "NIGHT_SLEEP") && event.endedAt) {
     return formatDuration(new Date(event.startedAt), new Date(event.endedAt));
   }