feat(deployment): implement recovery for interrupted rebuilds

tests/backend/deployment-recovery.test.ts

@@ -0,0 +1,47 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { classifyInterruptedRebuild } from "../../src/server/services/deployment-recovery.service";
+import { isDeploymentLockActive } from "../../src/server/services/deployment-lock.service";
+
+const startedAt = new Date("2026-08-22T10:00:00.000Z");
+
+test("interrupted rebuild is recovered as successful for a new running container", () => {
+  assert.equal(
+    classifyInterruptedRebuild({
+      startedAt,
+      inspect: {
+        Created: "2026-08-22T10:00:05.000Z",
+        State: { Running: true, Status: "running" },
+      },
+    }),
+    "SUCCESS",
+  );
+});
+
+test("interrupted rebuild is not reported as successful for the old runtime", () => {
+  assert.equal(
+    classifyInterruptedRebuild({
+      startedAt,
+      inspect: {
+        Created: "2026-08-20T10:00:00.000Z",
+        State: { Running: true, Status: "running" },
+      },
+    }),
+    "FAILED",
+  );
+});
+
+test("deployment lock becomes inactive when its heartbeat is stale", () => {
+  const now = new Date("2026-08-22T10:05:00.000Z");
+
+  assert.equal(
+    isDeploymentLockActive(
+      {
+        expiresAt: new Date("2026-08-22T10:15:00.000Z"),
+        updatedAt: new Date("2026-08-22T10:00:00.000Z"),
+      },
+      { now, staleMs: 120_000 },
+    ),
+    false,
+  );
+});