Report unsupported military track history in get_aircraft_track

The standalone military source no longer has getTrack, so the MCP
get_aircraft_track tool threw a TypeError and MCP advised a retry. It
now returns an `unsupported` ToolError when the selected feed has no
getTrack, while custom sources that supply history still work. Tests
cover the default composition through the catalog and MCP.

Also drop the unused epoch import and update the CURRENT-STATE track
sections to describe local trails and 503 history_unavailable.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/tools/queries/aviation.js

@@ -333,13 +333,20 @@ export const getAircraftTrack = defineTool({
   requires: ['aircraft'],
   async run(args, { services, signal }) {
     const icao24 = args.icao24.toLowerCase();
+    const source = feedFor(services, args.military);
+    // History is optional: the standalone military source has none.
+    if (typeof source.getTrack !== 'function')
+      throw new ToolError(
+        'unsupported',
+        args.military
+          ? 'Track history is not available for the military aircraft feed'
+          : 'Track history is not available for the aircraft feed',
+      );
     // A track server answers 404 for an aircraft it has no positions for.
-    const track = await feedFor(services, args.military)
-      .getTrack(icao24, { signal })
-      .catch((error) => {
-        if (error?.status === 404) return { records: [] };
-        throw error;
-      });
+    const track = await source.getTrack(icao24, { signal }).catch((error) => {
+      if (error?.status === 404) return { records: [] };
+      throw error;
+    });
     const points = [...track.records].sort(
       (a, b) => a.observedAtMs - b.observedAtMs,
     );