* this structure is never mutated, it provides a thread-safe view of the backing map.
 *
 * <p>The {@link MapIteratorCache} assumes ownership of the backing map, and cannot guarantee
 * correctness in the face of external mutations to the backing map. As such, it is <b>strongly</b>
 * recommended that the caller does not persist a reference to the backing map (unless the backing
 * map is immutable).
 *

        assertFalse(a.equals(null), "equals(null) should be false");
        assertFalse(a.equals("not a blob"), "equals(other type) should be false");
    }

    // Ensures clone() returns a deep copy; mutations are independent across instances
    @Test
    @DisplayName("clone: returns deep copy and independent state")
    void clone_returnsDeepCopy() {
        // Arrange
        byte[] data = new byte[] { 10, 20, 30 };