Add timezone preference across time displays

src/routes/betas/[id]/+page.svelte

@@ -1,4 +1,5 @@
 <script lang="ts">
+    import { timeFormat } from '$ui/stores/time-zone.js';
     import { onMount } from 'svelte';
     import { page } from '$app/stores';
     import { artifactVersionLabel } from '$lib/artifact-version.js';
@@ -129,9 +130,9 @@
         <div class="summary-heading"><h2>{closed ? beta.state === 'promoted' ? 'Version promoted' : 'Beta rolled back' : `${passed} / ${servers.length} servers passed`}</h2>{#if test}<span>{coverageSummary(test.plan)}</span>{/if}</div>
         <p>{nextAction}</p>
         {#if test?.reason}<p class="reason">{test.reason}</p>{/if}
-        <div class="timing"><span>Started <time datetime={beta.opened_at}>{new Date(beta.opened_at).toLocaleString()}</time></span>
-            {#if deadline && !closed}<strong>Ends <time datetime={deadline.toISOString()}>{deadline.toLocaleString()}</time> · {deadlineText}</strong>{/if}
-            {#if beta.closed_at}<span>Finished {new Date(beta.closed_at).toLocaleString()}</span>{/if}
+        <div class="timing"><span>Started <time datetime={beta.opened_at}>{$timeFormat.dateTime(beta.opened_at)}</time></span>
+            {#if deadline && !closed}<strong>Ends <time datetime={deadline.toISOString()}>{$timeFormat.dateTime(deadline)}</time> · {deadlineText}</strong>{/if}
+            {#if beta.closed_at}<span>Finished {$timeFormat.dateTime(beta.closed_at)}</span>{/if}
         </div>
         {#if !closed && test}<p class="muted">Waiting for empty servers uses this window. Pausing or retrying does not extend the deadline.</p>{/if}
         <div class="actions">
@@ -163,7 +164,7 @@
     {#if preview}
         <p><strong>{preview.servers.filter(server => server.tested).length} tested servers</strong> and <strong>{preview.servers.filter(server => !server.tested).length} additional eligible servers</strong>.</p>
         <p>Files are installed when you confirm. Tested servers have already restarted. Additional servers restart when empty, then their health is checked. Eligibility is determined by each file's current scope.</p>
-        <p class="muted">Reviewed {new Date(preview.createdAt).toLocaleString()}. If targets, versions, or composed settings change, you must review again.</p>
+        <p class="muted">Reviewed {$timeFormat.dateTime(preview.createdAt)}. If targets, versions, or composed settings change, you must review again.</p>
         {#each preview.blockers as blocker}<p class="ui-error" role="alert">{blocker}</p>{/each}
         <div class="file-list">{#each preview.files as file}<details open><summary>{file.name} · {artifactVersionLabel(file)} · {file.servers.length} servers</summary><p><code>{file.path}</code> · {file.scope} · SHA {file.sha256.slice(0,12)}</p><ul>{#each file.servers as name}<li><ServerIdentity {name}/><span>{preview.servers.find(server => server.name === name)?.tested ? 'Already tested' : 'Additional target · restart when empty'}</span></li>{/each}</ul></details>{/each}</div>
         {#if preview.configWrites.length}<details><summary>Composed configuration files ({preview.configWrites.length})</summary>{#each preview.configWrites as write}<p>{write.server} · {write.path} · {write.sha256?.slice(0,12) ?? write.error}</p>{/each}</details>{/if}