@Test
  public void testStartStopState() throws StoreException {
    assertTrue("FileStore should be running after start", fileStore.isRunning());
    fileStore.stop();
    assertFalse("FileStore should not be running after stop", fileStore.isRunning());
    fileStore.start(SEGMENT_CAPACITY);
    assertTrue("FileStore should be running after restart", fileStore.isRunning());
  }
Tests start/stop state transitions of FileStore.
Verifies running state is correctly tracked.
ambry-store/src/test/java/com/github/ambry/store/FileStoreTest.java