Add timezone preference across time displays

src/lib/ui/components/TelemetryDiagnostics.svelte

@@ -1,4 +1,5 @@
 <script lang="ts">
+    import { timeFormat } from '$ui/stores/time-zone.js';
     import { onMount } from 'svelte';
     import { TELEMETRY_REQUEST_RETENTION, type TelemetryRequestLogEntry } from '$lib/telemetry-diagnostics.js';
     import { pollVisible } from '$ui/poll.js';
@@ -61,10 +62,7 @@
     });
 
     function timestamp(value: string): string {
-        return new Date(value).toLocaleString(undefined, {
-            year: 'numeric', month: 'short', day: 'numeric',
-            hour: '2-digit', minute: '2-digit', second: '2-digit', timeZoneName: 'short'
-        });
+        return $timeFormat.dateTime(value);
     }
 
     function outcome(status: number): string {