fix: refresh buttons use "now" as to-date for queries

Instead of calling refetch() with stale time params, the refresh
buttons now set a toOverride state to new Date().toISOString(). This
flows into the query key, triggering a fresh fetch with the current
time as the upper bound. Both useApplicationLogs and useAgentEvents
hooks accept an optional toOverride parameter.

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

ui/src/pages/AgentHealth/AgentHealth.tsx

@@ -223,8 +223,9 @@ function AgentPerformanceContent({ agent }: { agent: AgentInstance }) {
 export default function AgentHealth() {
   const { appId } = useParams();
   const { data: agents } = useAgents(undefined, appId);
-  const { data: events, refetch: refetchEvents } = useAgentEvents(appId);
   const [eventSortAsc, setEventSortAsc] = useState(false);
+  const [eventRefreshTo, setEventRefreshTo] = useState<string | undefined>();
+  const { data: events } = useAgentEvents(appId, undefined, 50, eventRefreshTo);
 
   const [selectedInstance, setSelectedInstance] = useState<AgentInstance | null>(null);
   const [panelOpen, setPanelOpen] = useState(false);
@@ -509,7 +510,7 @@ export default function AgentHealth() {
               <button className={styles.sortBtn} onClick={() => setEventSortAsc((v) => !v)} title={eventSortAsc ? 'Oldest first' : 'Newest first'}>
                 {eventSortAsc ? '\u2191' : '\u2193'}
               </button>
-              <button className={styles.refreshBtn} onClick={() => refetchEvents()} title="Refresh">
+              <button className={styles.refreshBtn} onClick={() => setEventRefreshTo(new Date().toISOString())} title="Refresh">
                 &#x21bb;
               </button>
             </div>

ui/src/pages/AgentInstance/AgentInstance.tsx

@@ -35,11 +35,13 @@ export default function AgentInstance() {
   const [logLevels, setLogLevels] = useState<Set<string>>(new Set());
   const [logSortAsc, setLogSortAsc] = useState(false);
   const [eventSortAsc, setEventSortAsc] = useState(false);
+  const [logRefreshTo, setLogRefreshTo] = useState<string | undefined>();
+  const [eventRefreshTo, setEventRefreshTo] = useState<string | undefined>();
   const timeFrom = timeRange.start.toISOString();
   const timeTo = timeRange.end.toISOString();
 
   const { data: agents, isLoading } = useAgents(undefined, appId);
-  const { data: events, refetch: refetchEvents } = useAgentEvents(appId, instanceId);
+  const { data: events } = useAgentEvents(appId, instanceId, 50, eventRefreshTo);
   const { data: timeseries } = useStatsTimeseries(timeFrom, timeTo, undefined, appId);
 
   const agent = useMemo(
@@ -137,7 +139,7 @@ export default function AgentInstance() {
   );
 
   // Application logs from OpenSearch
-  const { data: rawLogs, refetch: refetchLogs } = useApplicationLogs(appId, instanceId);
+  const { data: rawLogs } = useApplicationLogs(appId, instanceId, { toOverride: logRefreshTo });
   const logEntries = useMemo<LogEntry[]>(() => {
     const mapped = (rawLogs || []).map((l) => ({
       timestamp: l.timestamp ?? '',
@@ -402,7 +404,7 @@ export default function AgentInstance() {
               <button className={styles.sortBtn} onClick={() => setLogSortAsc((v) => !v)} title={logSortAsc ? 'Oldest first' : 'Newest first'}>
                 {logSortAsc ? '\u2191' : '\u2193'}
               </button>
-              <button className={styles.refreshBtn} onClick={() => refetchLogs()} title="Refresh">
+              <button className={styles.refreshBtn} onClick={() => setLogRefreshTo(new Date().toISOString())} title="Refresh">
                 &#x21bb;
               </button>
             </div>
@@ -452,7 +454,7 @@ export default function AgentInstance() {
               <button className={styles.sortBtn} onClick={() => setEventSortAsc((v) => !v)} title={eventSortAsc ? 'Oldest first' : 'Newest first'}>
                 {eventSortAsc ? '\u2191' : '\u2193'}
               </button>
-              <button className={styles.refreshBtn} onClick={() => refetchEvents()} title="Refresh">
+              <button className={styles.refreshBtn} onClick={() => setEventRefreshTo(new Date().toISOString())} title="Refresh">
                 &#x21bb;
               </button>
             </div>