refactor: move infrastructure data parsing into a portable source module

The datacenter and dam layers parsed their bundled GeoJSON Lines and
built analyst records inside the Cesium-backed layer module. Move the
data URLs, the line parser, mapAnalystRecord and layerTitle unchanged to
src/sources/infrastructureData.js; the layer module imports them and
still exports mapAnalystRecord. The consumer-build pin lists the new
module.

src/data/infrastructure.test.mjs

@@ -192,6 +192,7 @@ test('consumer build includes only infrastructure code and resolves assets under
   const sources = Object.keys(entry.modules).filter((id) => id.endsWith('.js'));
   assert.deepEqual(sources.map((id) => id.split('/').at(-1)).sort(), [
     'infrastructure.js',
+    'infrastructureData.js',
     'infrastructureOverlayEntry.js',
     'localGeojsonCore.js',
     'localGeojsonLod.js',