Preserve deleted server history

Retain historical server identities, results, and evidence after deletion. Mark archived entries as Deleted and prevent old work from targeting servers that reuse the same name.

Fixes #16.

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

@@ -17,6 +17,9 @@ export async function POST({ params, request }: { params: { id: string }; reques
     if (!['running', 'ready-promote'].includes(beta.state)) return json({ error: 'Beta is closed' }, { status: 409 });
     try {
         const body = await request.json();
+        if (db().prepare('SELECT 1 FROM beta_servers WHERE beta_id = ? AND server_deleted_at IS NOT NULL').get(id)) {
+            return json({ ok: false, error: 'A beta server was deleted. Roll back this beta and open a new one to collect fresh evidence.' }, { status: 409 });
+        }
         const plan = parseBetaPlan(JSON.parse(stored.plan));
         if (body.action === 'sign-off') {
             if (!['active', 'passed'].includes(stored.outcome)) throw new Error('Resume or retry the test before signing off');