[JVM IR] Copy metadata in IrFieldBuilder.

This fixes an issue with lateinit properties where the metadata from
the original field was not copied to the nullable field in
LateinitLowering. Also consolidated related tests.

compiler/testData/codegen/box/reflection/mapping/lateinitProperty.kt

@@ -0,0 +1,33 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM
+
+// WITH_REFLECT
+
+import kotlin.reflect.jvm.*
+import kotlin.test.*
+
+class K {
+    lateinit var value: String
+}
+
+fun box(): String {
+    val p = K::value
+
+    assertNotNull(p.javaField, "Fail p field")
+
+    val getter = p.javaGetter!!
+    val setter = p.javaSetter!!
+
+    assertEquals(K::class.java.getMethod("getValue"), getter)
+    assertEquals(K::class.java.getMethod("setValue", String::class.java), setter)
+
+    assertNull(p.getter.javaConstructor)
+    assertNull(p.setter.javaConstructor)
+
+    val k = K()
+    assertFails("Fail k getter") { getter.invoke(k) }  // lateinit not yet initialized
+    setter.invoke(k, "foo")
+    assertEquals("foo", getter.invoke(k), "Fail k setter")
+
+    return "OK"
+}