Make UI language, timestamps and live feedback consistent

src/routes/betas/+page.svelte

@@ -1,4 +1,5 @@
 <script lang="ts">
+    import RelativeTime from '$ui/components/RelativeTime.svelte';
     import { page } from '$app/stores';
     import { contextHref } from '$lib/navigation-context.js';
     import { timeFormat } from '$ui/stores/time-zone.js';
@@ -44,7 +45,6 @@
     const tabs = $derived([{id:'active',label:'Active',badge:counts.active},{id:'history',label:'History',badge:counts.history}]);
     let now = $state(Date.now());
 
-    function age(date:string) { const minutes=Math.max(0,Math.floor((now-Date.parse(date))/60000));return minutes<60?`${minutes}m ago`:minutes<1440?`${Math.floor(minutes/60)}h ago`:`${Math.floor(minutes/1440)}d ago`; }
     function deadlineLabel(beta: BetaListRow) {
         if (!beta.deadlineAt || !active(beta) || beta.testOutcome === 'passed') return '';
         const minutes = Math.ceil((Date.parse(beta.deadlineAt) - now) / 60000);
@@ -121,7 +121,7 @@
                         <td><a class="beta-link" href={contextHref('/betas/' + beta.id, $page.url)}>{beta.notes || `Beta #${beta.id}`}</a>{#if beta.notes}<span class="beta-id">#{beta.id}</span>{/if}</td>
                         <td class="files">{#if beta.scripts.length === 1}{beta.scripts[0].name} <span>{artifactVersionLabel(beta.scripts[0].version)}</span>{:else}{beta.scripts.length} files{/if}</td>
                         <td><Badge variant={presentation.tone} size="md">{presentation.label}</Badge>{#if expiry}<span class="expiry">{expiry}</span>{/if}</td>
-                        <td class="started"><button type="button" class="timestamp" aria-label={`Started ${$timeFormat.dateTime(beta.opened_at)}`}><time datetime={beta.opened_at}>{age(beta.opened_at)}</time><span class="exact-time" aria-hidden="true">{$timeFormat.dateTime(beta.opened_at)}</span></button></td>
+                        <td class="started"><button type="button" class="timestamp" aria-label={`Started ${$timeFormat.dateTime(beta.opened_at)}`}><RelativeTime value={beta.opened_at} /><span class="exact-time" aria-hidden="true">{$timeFormat.dateTime(beta.opened_at)}</span></button></td>
                     </tr>
                 {/each}</tbody>
             </table></div>