migration to 2.0. New version with reinforced signed box to include timestamp and expiration

src/commonTest/kotlin/KeysTest.kt

@@ -23,10 +23,10 @@ class KeysTest {
         val data = "8 rays dev!".encodeToUByteArray()
         val data1 = "8 rays dev!".encodeToUByteArray()
         val s = stk.seal(data)
-        assertTrue(s.verify(data))
+        s.verify(data)
 
         data1[0] = 0x01u
-        assertFalse(s.verify(data1))
+        assertFalse(s.isValid(data1))
         val p2 = SigningKey.pair()
         val p3 = SigningKey.pair()