feat: ship verified platform upgrades with channel bundle releases

Package production dependencies per architecture for online and offline upgrades.
Validate dependencies and isolated backend startup before readiness, repair once
when permitted, and preserve service/data through failed preparation or rollback.

Publish release bundles with master images and expose an opt-in develop build
sharing the development index across Alpine and Debian images.

test/back/upgrade-guards.test.cjs

@@ -283,3 +283,54 @@ test('unhealthy, malformed and oversized health responses fail within the deadli
     await assert.rejects(waitForHealth({ QlPort: port }, 20), /health check|后端启动检查失败/);
   }
 });
+
+test('ARMv6 startup can become healthy after the standard one-minute deadline', async (t) => {
+  const { EventEmitter } = require('node:events');
+  const descriptors = ['arch', 'config'].map((key) => [
+    key,
+    Object.getOwnPropertyDescriptor(process, key),
+  ]);
+  t.after(() => {
+    for (const [key, descriptor] of descriptors)
+      Object.defineProperty(process, key, descriptor);
+  });
+  Object.defineProperty(process, 'arch', { value: 'arm', configurable: true });
+  Object.defineProperty(process, 'config', {
+    value: { variables: { arm_version: 6 } },
+    configurable: true,
+  });
+  let now = 0;
+  let probes = 0;
+  t.mock.method(Date, 'now', () => now);
+  t.mock.method(http, 'get', (_options, callback) => {
+    const request = new EventEmitter();
+    request.destroy = (error) => request.emit('error', error);
+    queueMicrotask(() => {
+      const response = new EventEmitter();
+      response.statusCode = ++probes === 1 ? 503 : 200;
+      callback(response);
+      now = probes * 70000;
+      response.emit(
+        'data',
+        JSON.stringify({
+          code: response.statusCode,
+          data: { status: probes > 1 ? 'ok' : 'starting' },
+        }),
+      );
+      response.emit('end');
+    });
+    return request;
+  });
+  await waitForHealth({});
+  assert.equal(probes, 2);
+  assert.equal(now, 140000);
+  const { startupHealthTimeout } = require('../../shell/upgrade.cjs');
+  assert.equal(
+    startupHealthTimeout({
+      arch: 'arm',
+      config: { variables: { arm_version: 7 } },
+    }),
+    60000,
+  );
+  assert.equal(startupHealthTimeout({ arch: 'arm64' }), 60000);
+});