[LL FIR] KT-58257 Invalidate library sessions depending on anchor modules on global source modification

- Any time an anchor module's session is invalidated, we need to make
  sure that all its dependents are also invalidated. Because those
  dependents may include libraries, invalidation after global source
  modification needs to invalidate such libraries, even if other stable
  module sessions should remain untouched.

analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/KotlinAnchorModuleProvider.kt

@@ -10,17 +10,22 @@ import org.jetbrains.kotlin.analysis.project.structure.KtLibraryModule
 import org.jetbrains.kotlin.analysis.project.structure.KtSourceModule
 
 /**
- * Provide module which contains dependencies of the library.
+ * [KotlinAnchorModuleProvider] provides modules which contain dependencies of libraries.
  *
- * Is required for navigation in IJ monorepo from kotlin compiler library sources to IJ platform sources.
- * Kotlin compiler depends on platform but this dependency is not represented as jars in monorepo
- * but should be replaced with given sources.
+ * In the IJ monorepo, anchor modules are required for navigation from Kotlin compiler library sources to IJ platform sources. The Kotlin
+ * compiler depends on the IJ platform, but this dependency is not represented as JARs in the monorepo, but rather by certain monorepo
+ * source modules, which are made visible to the Kotlin compiler library sources as dependencies via an anchor module.
  */
 public interface KotlinAnchorModuleProvider {
     public fun getAnchorModule(libraryModule: KtLibraryModule): KtSourceModule?
 
+    /**
+     * Returns all anchor modules configured in the project.
+     */
+    public fun getAllAnchorModules(): Collection<KtSourceModule>
+
     public companion object {
         public fun getInstance(project: Project): KotlinAnchorModuleProvider? =
             project.getService(KotlinAnchorModuleProvider::class.java)
     }
-}
+}