FIR IDE: introduce KtFirArrayAccessReference

compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/RawFirBuilder.kt

@@ -1790,16 +1790,17 @@ class RawFirBuilder(
                 if (getArgument != null) {
                     calleeReference = buildSimpleNamedReference {
                         source = expression.parent.toFirSourceElement()
-                        this.source = source
+                        this.source = source.fakeElement(FirFakeSourceElementKind.ArrayAccessNameReference)
                         name = OperatorNameConventions.SET
                     }
                 } else {
                     source = expression.toFirSourceElement()
                     calleeReference = buildSimpleNamedReference {
-                        this.source = source
+                        this.source = source.fakeElement(FirFakeSourceElementKind.ArrayAccessNameReference)
                         name = OperatorNameConventions.GET
                     }
                 }
+                this.source = source
                 explicitReceiver = arrayExpression.toFirExpression("No array expression")
                 argumentList = buildArgumentList {
                     for (indexExpression in expression.indexExpressions) {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirSourceElement.kt

@@ -139,6 +139,9 @@ sealed class FirFakeSourceElementKind : FirSourceElementKind() {
     // where `val $subj = a` has a fake source
     object WhenGeneratedSubject : FirFakeSourceElementKind()
 
+    // list[0] -> list.get(0) where name reference will have a fake source element
+    object ArrayAccessNameReference : FirFakeSourceElementKind()
+
     // super.foo() --> super<Supertype>.foo()
     // where `Supertype` has a fake source
     object SuperCallImplicitType : FirFakeSourceElementKind()