Refactor and enhance tests for call graph extractors and connection management

- Updated JavaScriptCallGraphExtractorTests to improve naming conventions and test cases for Azure Functions, CLI commands, and socket handling.
- Modified NodeCallGraphExtractorTests to correctly assert exceptions for null inputs.
- Enhanced WitnessModalComponent tests in Angular to use Jasmine spies and improved assertions for path visualization and signature verification.
- Added ConnectionState property for tracking connection establishment time in Router.Common.
- Implemented validation for HelloPayload in ConnectionManager to ensure required fields are present.
- Introduced RabbitMqContainerFixture method for restarting RabbitMQ container during tests.
- Added integration tests for RabbitMq to verify connection recovery after broker restarts.
- Created new BinaryCallGraphExtractorTests, GoCallGraphExtractorTests, and PythonCallGraphExtractorTests for comprehensive coverage of binary, Go, and Python call graph extraction functionalities.
- Developed ConnectionManagerTests to validate connection handling, including rejection of invalid hello messages and proper cleanup on client disconnects.

src/Scanner/__Tests/StellaOps.Scanner.CallGraph.Tests/NodeCallGraphExtractorTests.cs

@@ -132,7 +132,7 @@ public class NodeCallGraphExtractorTests
     {
         // Arrange & Act & Assert
         Assert.Throws<ArgumentException>(() => BabelResultParser.Parse(""));
-        Assert.Throws<ArgumentException>(() => BabelResultParser.Parse(null!));
+        Assert.Throws<ArgumentNullException>(() => BabelResultParser.Parse(null!));
     }
 
     [Fact]