feat(appservice): mosaic-as daemon host + container (M4a) (#531)

apps/appservice/src/registration-main.ts

@@ -0,0 +1,10 @@
+import { buildRegistration, registrationToYaml } from '@mosaicstack/appservice';
+
+import { configFromEnv } from './config.js';
+
+// Prints the Synapse registration YAML (mosaic-as.yaml) for the current env.
+// Usage: MOSAIC_AS_URL=http://mosaic-as:8008 mosaic-as-registration > mosaic-as.yaml
+const cfg = configFromEnv();
+const url = process.env.MOSAIC_AS_URL;
+if (!url) throw new Error('missing required env var MOSAIC_AS_URL');
+process.stdout.write(registrationToYaml(buildRegistration(cfg, { url })));