FIR IDE: build KtJavaFieldSymbol only for Java fields

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirFieldBuilder.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.builder
 
 import kotlin.contracts.*
+import org.jetbrains.kotlin.fir.FirImplementationDetail
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
@@ -51,6 +52,7 @@ open class FirFieldBuilder : FirAnnotationContainerBuilder {
     open var containerSource: DeserializedContainerSource? = null
     open var dispatchReceiverType: ConeKotlinType? = null
 
+    @OptIn(FirImplementationDetail::class)
     override fun build(): FirField {
         return FirFieldImpl(
             source,

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirFieldImpl.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.fir.declarations.impl
 
+import org.jetbrains.kotlin.fir.FirImplementationDetail
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationAttributes
@@ -29,7 +30,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-internal class FirFieldImpl(
+class FirFieldImpl @FirImplementationDetail constructor(
     override val source: FirSourceElement?,
     override val session: FirSession,
     override var resolvePhase: FirResolvePhase,

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/ImplementationConfigurator.kt

@@ -209,6 +209,7 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
                 value = "!isVar"
                 withGetter = true
             }
+            publicImplementation()
 
             defaultNull("delegateFieldSymbol", "receiverTypeRef", "delegate", "getter", "setter", withGetter = true)
         }