fix: correct SearchRequest field names (offset/limit, sortField/sortDir)

Dashboard was sending page/size but backend expects offset/limit.
Schema also had sort/order instead of sortField/sortDir.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/pages/Dashboard/Dashboard.tsx

@@ -27,7 +27,7 @@ export default function Dashboard() {
     timeFrom, timeTo,
     routeId: routeId || undefined,
     group: appId || undefined,
-    page: 0, size: 50,
+    offset: 0, limit: 50,
   }, true);
   const { data: detail } = useExecutionDetail(selectedId);
   const { data: snapshot } = useProcessorSnapshot(selectedId, processorIdx);