FIR: Introduce CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT diagnostic

compiler/fir/analysis-tests/testData/resolve/constVal/constValNotTopLevelOrObject.kt

@@ -0,0 +1,42 @@
+const val a = 1
+
+object B {
+    const val b = 2
+}
+
+class C {
+    <!CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT!>const<!> val c = 3
+}
+
+class D {
+    object E {
+        const val e = 4
+    }
+
+    companion object K {
+        const val k = 4
+    }
+
+    val M = object {
+        <!CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT!>const<!> val m = 3
+    }
+
+    open class O {
+        open val y: Int = 8
+    }
+
+    val t: O = object : O() {
+        <!CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT!>const<!> val x = 15
+    }
+
+}
+
+object F {
+    class G {
+        <!CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT!>const<!> val e = 4
+    }
+}
+
+fun foo() {
+    <!CONST_VAL_NOT_TOP_LEVEL_OR_OBJECT!>const<!> val a = "2"
+}