[FIR] Do not include transitive friend dependencies in symbol provider

When flattening a dependency FirSymbolProvider, make sure transitive
dependency FirSymbolProviders are not included. This requires checking
that nested symbol provider sessions match the composite symbol provider
session when they are both source sessions.

^KT-60614 Fixed

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java

@@ -23266,6 +23266,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
                 KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multimodule"), Pattern.compile("^(.+)\\.(kt|kts)$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
             }
 
+            @Test
+            @TestMetadata("dependencyModule.kt")
+            public void testDependencyModule() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multimodule/dependencyModule.kt");
+            }
+
             @Test
             @TestMetadata("dependsOnModule.kt")
             public void testDependsOnModule() throws Exception {

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java

@@ -23266,6 +23266,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
                 KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/multimodule"), Pattern.compile("^(.+)\\.(kt|kts)$"), Pattern.compile("^(.+)\\.(reversed|fir|ll)\\.kts?$"), true);
             }
 
+            @Test
+            @TestMetadata("dependencyModule.kt")
+            public void testDependencyModule() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multimodule/dependencyModule.kt");
+            }
+
             @Test
             @TestMetadata("dependsOnModule.kt")
             public void testDependsOnModule() throws Exception {