release: v2.1.12 reliability and security hardening

Verify update artifacts with exact metadata and SHA-512, require host-confirmed upload completion before cleanup, harden credentials and backups, improve queue recovery and skipped-state reporting, expand Windows path coverage, and add CI packaging checks.

tests/queue-stats.test.js

@@ -0,0 +1,23 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const { calculateQueueStats } = require('../renderer/queue-stats');
+
+test('queue totals keep skipped and aborted jobs out of remaining work', () => {
+  const stats = calculateQueueStats([
+    { status: 'done', bytesTotal: 100, bytesUploaded: 100 },
+    { status: 'error', bytesTotal: 100, bytesUploaded: 20 },
+    { status: 'skipped', bytesTotal: 100, bytesUploaded: 0 },
+    { status: 'aborted', bytesTotal: 100, bytesUploaded: 10 },
+    { status: 'queued', bytesTotal: 100, bytesUploaded: 0 },
+    { status: 'uploading', bytesTotal: 100, bytesUploaded: 40 }
+  ]);
+  assert.deepEqual({ total: stats.total, remaining: stats.remaining, done: stats.done, errors: stats.errors, skipped: stats.skipped, aborted: stats.aborted }, {
+    total: 6,
+    remaining: 2,
+    done: 1,
+    errors: 1,
+    skipped: 1,
+    aborted: 1
+  });
+  assert.equal(stats.remainingSize, 160);
+});