Add multi-server blueprint collections and atomic launches

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

@@ -14,7 +14,7 @@
         stage: string; started_at: string; finished_at: string | null;
         triggered_by: string; error: string | null; warnings: string; server_exists: number;
     }
-    interface Detail { deployment: Deployment; events: { id: number; created_at: string; message: string }[]; recipe: LaunchRecipeSummary | null; blueprintName: string | null; canResumeVerification: boolean }
+    interface Detail { deployment: Deployment; events: { id: number; created_at: string; message: string }[]; recipe: LaunchRecipeSummary | null; blueprintName: string | null; canResumeVerification: boolean; collection: { id: string; name: string } | null }
     let detail = $state<Detail | null>(null);
     let error = $state('');
     let refreshing = false;
@@ -102,6 +102,7 @@
         {#snippet crumbs()}<Breadcrumbs items={[{ label: 'Deployments', href: '/deployments' }, { label: deployment?.server ?? 'Details' }]} />{/snippet}
     </SectionHeader>
     {#if error}<p role="alert" class="error">{error} <button onclick={load}>Retry</button></p>{/if}
+    {#if detail?.collection}<a href="/deployments/collections/{detail.collection.id}">← Back to {detail.collection.name} collection</a>{/if}
     {#if deployment}
         <section class="summary">
             <div class="top"><Badge variant={deployment.state === 'done' ? 'online' : deployment.state === 'failed' ? 'danger' : 'warning'}>{stateLabel(deployment.state)}</Badge>