refactor: construct application layers from supplied sources

src/app/layers/militaryInstallations.js

@@ -0,0 +1,14 @@
+import { createInstallationsLayer } from '../../layers/installations/index.js';
+import * as render from '../../renderGovernor.js';
+import * as context from '../../data/contextStore.js';
+import * as ground from '../../data/groundFloor.js';
+import * as anchors from '../../data/fireAnchors.js';
+import * as picking from '../../data/pickRegistry.js';
+
+/** Construct one layer using the application scene owners and a supplied source. */
+export function createApplicationInstallations({ source }) {
+  return createInstallationsLayer({
+    source,
+    services: { render, context, ground, anchors, picking },
+  });
+}