chore: remove unreachable legacy entry modules

Delete three modules that no entry point, package export, test or script
imports:

- src/ui.js, a StyleManager subclass that pre-selected the standalone
  catalog. Application controls are built through src/app/controls.js
  and src/standalone/controls.js.
- src/standalone/ui.js, a bare re-export of StyleManager.
- src/data/localLayers.js, a list of default infrastructure, cable and
  FIRMS layer instances. The catalog builds these layers itself.

With src/ui.js gone, the import-direction check keeps a single
compatibility exception (server/providers/local.js to
server/standalone/key-setup.js), and its test now asserts that a
src/ui.js importing standalone code is rejected. The boundary and
format registries and the docs that named these files are updated.

scripts/check-import-directions.mjs

@@ -24,11 +24,10 @@ const renderer = (file) =>
   /^src\/layers\/[^/]+\/(?:index|rendering|snapshotRenderer|overlay|presentation|cards|controls)\.js$/.test(
     file,
   );
-// Two compatibility composition entries intentionally select standalone defaults.
+// One compatibility composition entry intentionally selects standalone defaults.
 const compatibilityEdge = (from, to) =>
-  (from === 'server/providers/local.js' &&
-    to === 'server/standalone/key-setup.js') ||
-  (from === 'src/ui.js' && to === 'src/standalone/catalog.js');
+  from === 'server/providers/local.js' &&
+  to === 'server/standalone/key-setup.js';
 const portableExport = (key) =>
   key.startsWith('./sources/') ||
   /\/source$/.test(key) ||