refactor: separate map feature queries and source records

src/layers/installations/source.test.mjs

@@ -57,3 +57,30 @@ test('installation response parsing respects cancellation before any follow-on s
     { name: 'AbortError' },
   );
 });
+
+test('mapped-site sources normalize records and derive saturation from legacy cache metadata', async () => {
+  const source = createInstallationSource({
+    fetchImpl: async () =>
+      Response.json({
+        elements: [
+          {
+            type: 'node',
+            id: 1,
+            lat: 30.2,
+            lon: -97.7,
+            tags: { military: 'airfield', name: 'Fixture Field' },
+          },
+        ],
+        elementCap: 1,
+        status: 'stale',
+        retrievedAt: '2026-01-01T00:00:00Z',
+      }),
+  });
+  const payload = await source.getMappedSites(box);
+  assert.equal(payload.records[0].name, 'Fixture Field');
+  assert.equal(payload.records[0].latitude, 30.2);
+  assert.equal(payload.records[0].retrievedAt, '2026-01-01T00:00:00Z');
+  assert.equal(payload.saturated, true);
+  assert.equal(payload.status, 'stale');
+  assert.equal('elements' in payload, false);
+});