feat(aihr): complete phase two pilot readiness

frontend/src/views/train/pilot-export.test.ts

@@ -0,0 +1,16 @@
+import { describe, expect, it } from 'vitest';
+
+import { resolvePilotDateWindow } from './pilot-export';
+
+describe('resolvePilotDateWindow', () => {
+  it('returns null when the Element Plus date range is cleared', () => {
+    expect(resolvePilotDateWindow(null)).toBeNull();
+  });
+
+  it('returns an explicit start and end date only for a complete range', () => {
+    expect(resolvePilotDateWindow(['2026-07-07', '2026-07-10'])).toEqual({
+      startDate: '2026-07-07',
+      endDate: '2026-07-10'
+    });
+  });
+});