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.

back/loaders/httpApplication.ts

@@ -0,0 +1,33 @@
+import type express from 'express';
+import config from '../config';
+
+export async function createHttpApplication(): Promise<express.Application> {
+  // Only the HTTP worker needs an Express application and its middleware.
+  const [
+    { default: createExpress },
+    { default: helmet },
+    { default: cors },
+    { default: compression },
+    { monitoringMiddleware },
+  ] = await Promise.all([
+    import('express'),
+    import('helmet'),
+    import('cors'),
+    import('compression'),
+    import('../middlewares/monitoring'),
+  ]);
+  const app = createExpress();
+  app.use((req, res, next) => {
+    if (req.query.t) delete req.query.t;
+    next();
+  });
+  app.use(
+    helmet({
+      contentSecurityPolicy: false,
+    }),
+  );
+  app.use(cors(config.cors));
+  app.use(compression());
+  app.use(monitoringMiddleware);
+  return app;
+}