[FIR2IR] Unwrap call-site substitution overrides

Generating IR declarations for use-site substitution overrides leads
to IR that is different from K1 as well as problems in signature
generation which relies on mangling. Use-site substitutions can contain
references to type parameters from the call-site which aren't handled
in mangling.

#KT-57022 Fixed

compiler/testData/ir/irText/firProblems/SignatureComputationComplexJavaGeneric.kt

@@ -1,21 +1,47 @@
+// FIR_IDENTICAL
 // TARGET_BACKEND: JVM_IR
+// ISSUE: KT-57022
 
-// MUTE_SIGNATURE_COMPARISON_K2: ANY
-// ^ KT-57022
-
-// FILE: J.java
+// FILE: JavaClass1.java
 
 import org.jetbrains.annotations.Nullable;
 
-public class J<T extends @Nullable Object> {
+public class JavaClass1<T extends @Nullable Object> {
     public class A {
         public void output(T x) {}
     }
-    public class B extends A {}
+    public class B extends A {
+    }
+}
+
+// FILE: JavaClass2.java
+import org.jetbrains.annotations.Nullable;
+
+public abstract class JavaClass2<T extends @Nullable Object, R extends @Nullable Object> {
+
+  public abstract class A {
+    public abstract void output(R output);
+  }
+
+  public abstract class B extends A {
+    public abstract T element();
+  }
 }
 
 // FILE: test.kt
 
-class Test<T>(val x: T) : J<T>() {
+class Inv<T>(val x: T)
+
+class Test_1<TT>(val x: TT) : JavaClass1<TT>() {
     fun test(b: B) { b.output(x) }
 }
+
+class Test_2<TT> : JavaClass2<TT, Inv<TT>>() {
+    fun process(b: B) {
+        b.output(Inv(b.element()))
+    }
+}
+
+fun <R> test_3(jb: JavaClass1<R>.B, r: R) {
+    jb.output(r)
+}