fix: keep aircraft search results when one feed is down

find_aircraft failed whenever either feed failed. It now answers from the
feeds that responded, names the ones that did not, and searches only the
military feed for registrations, the only feed that reports them.

src/tools/queries/aviation.test.mjs

@@ -298,3 +298,42 @@ test('live source failures become tool errors with retry guidance', async () =>
       error.message === 'OpenSky rate limited',
   );
 });
+
+test('aircraft searches keep the feeds that answered and name the others', async () => {
+  const down = {
+    getSnapshot: async () => {
+      throw new LiveSourceError('unavailable', 'OpenSky HTTP 503');
+    },
+  };
+  const military = feed([
+    record('ae1234', 38, -77, { callsign: 'RCH123', registration: '05-5140' }),
+  ]);
+  const catalog = composeCatalog({
+    tools: coreTools,
+    services: { aircraft: down, military },
+  });
+  const byCallsign = await catalog.call('find_aircraft', {
+    callsign: 'rch123',
+  });
+  assert.equal(
+    byCallsign.summary,
+    'Found 1 aircraft with callsign RCH123. The civil feed did not answer.',
+  );
+  assert.deepEqual(byCallsign.data.unavailable_feeds, ['civil']);
+  const civil = feed([]);
+  const byRegistration = await composeCatalog({
+    tools: coreTools,
+    services: { aircraft: civil, military },
+  }).call('find_aircraft', { registration: '05-5140' });
+  assert.equal(byRegistration.data.rows[0].id, 'ae1234');
+  assert.deepEqual(byRegistration.data.unavailable_feeds, []);
+  assert.equal(civil.calls.length, 0);
+  await assert.rejects(
+    composeCatalog({
+      tools: coreTools,
+      services: { aircraft: down, military: down },
+    }).call('find_aircraft', { callsign: 'RCH123' }),
+    (error) =>
+      error.code === 'unavailable' && error.message === 'OpenSky HTTP 503',
+  );
+});