[AA] KT-58580 Add KotlinDeclarationProviderMerger

- A proper merging strategy for declaration providers is required for
  cases where the main declaration provider created by
  `createDeclarationProvider` can't provide all declarations that the
  original declaration providers can provide. Then, only a sublist of
  the declaration providers should be merged, while keeping the
  unmergeable declaration providers intact.

^KT-58580 fixed

analysis/analysis-api-standalone/src/org/jetbrains/kotlin/analysis/api/standalone/StandaloneAnalysisAPISessionBuilder.kt

@@ -141,6 +141,7 @@ public class StandaloneAnalysisAPISessionBuilder(
                     kotlinCoreProjectEnvironment.environment.jarFileSystem as CoreJarFileSystem
                 )
             )
+            registerService(KotlinDeclarationProviderMerger::class.java, KotlinStaticDeclarationProviderMerger(this))
             registerService(KotlinPackageProviderFactory::class.java, KotlinStaticPackageProviderFactory(project, ktFiles))
 
             registerService(KtAnalysisSessionProvider::class.java, KtFirAnalysisSessionProvider(this))

analysis/analysis-api-standalone/src/org/jetbrains/kotlin/analysis/api/standalone/StandaloneUtils.kt

@@ -159,6 +159,10 @@ internal fun configureProjectEnvironment(
         KotlinDeclarationProviderFactory::class.java,
         KotlinStaticDeclarationProviderFactory(project, ktFiles)
     )
+    project.registerService(
+        KotlinDeclarationProviderMerger::class.java,
+        KotlinStaticDeclarationProviderMerger(project)
+    )
     project.registerService(
         KotlinPackageProviderFactory::class.java,
         KotlinStaticPackageProviderFactory(project, ktFiles)