Improve operational UX, recovery flows, and action safety

Implement the approved UX review across Fleet, Betas, Library, deployments, and Settings. Add reviewed promotion and reconciliation plans, atomic queued-removal cancellation, recoverable beta drafts and launch inputs, accessible controls, and mobile improvements.

Validated with 473 tests, a clean typecheck, production build, and isolated desktop/mobile browser walkthroughs. Include the review and implementation coverage notes.

src/routes/api/betas/[id]/+server.ts

@@ -31,5 +31,9 @@ export async function GET({ params }: { params: { id: string } }) {
     const servers = listBetaServers(id);
 
     const events = db().prepare('SELECT id, created_at, message FROM beta_events WHERE beta_id = ? ORDER BY id').all(id);
-    return json({ beta, scripts, servers, events, test: testView(id) });
+    const rollout = db().prepare("SELECT id FROM deployments WHERE beta_id = ? AND action = 'promote' ORDER BY started_at DESC LIMIT 1").get(id) as { id: string } | undefined;
+    const promotion = rollout ? { ...rollout,
+        pending: (db().prepare("SELECT COUNT(*) n FROM deployment_servers WHERE deployment_id = ? AND restart_state NOT IN ('done','failed','cancelled')").get(rollout.id) as { n: number }).n,
+        failed: (db().prepare("SELECT COUNT(*) n FROM deployment_servers WHERE deployment_id = ? AND restart_state = 'failed'").get(rollout.id) as { n: number }).n } : null;
+    return json({ beta, scripts, servers, events, test: testView(id), promotion });
 }

src/routes/api/betas/[id]/promote/+server.ts

@@ -1,16 +1,28 @@
 import { json } from '@sveltejs/kit';
-import { promoteBeta, BetaError } from '$lib/server/fleet/beta.js';
+import { promoteBeta, previewBetaPromotion, BetaError } from '$lib/server/fleet/beta.js';
 
 function parseId(raw: string): number | null {
     const n = Number.parseInt(raw, 10);
     return Number.isFinite(n) ? n : null;
 }
 
-export async function POST({ params }: { params: { id: string } }) {
+export async function GET({ params }: { params: { id: string } }) {
+    const id = parseId(params.id);
+    if (id === null) return json({ ok: false, error: 'Invalid beta ID.' }, { status: 400 });
+    try { return json({ preview: previewBetaPromotion(id) }, { headers: { 'Cache-Control': 'no-store' } }); }
+    catch (err) {
+        if (err instanceof BetaError) return json({ error: err.message }, { status: 409 });
+        throw err;
+    }
+}
+
+export async function POST({ params, request }: { params: { id: string }; request: Request }) {
     const id = parseId(params.id);
     if (id === null) return json({ ok: false, error: 'bad id' }, { status: 400 });
+    const body = await request.json().catch(() => null);
+    if (typeof body?.previewToken !== 'string') return json({ ok: false, error: 'Review promotion targets before confirming.' }, { status: 400 });
     try {
-        const result = await promoteBeta(id);
+        const result = await promoteBeta(id, body.previewToken);
         return json({ ok: true, result });
     } catch (err) {
         if (err instanceof BetaError) {