feat: add stella-callgraph-node for JavaScript/TypeScript call graph extraction

- Implemented a new tool `stella-callgraph-node` that extracts call graphs from JavaScript/TypeScript projects using Babel AST.
- Added command-line interface with options for JSON output and help.
- Included functionality to analyze project structure, detect functions, and build call graphs.
- Created a package.json file for dependency management.

feat: introduce stella-callgraph-python for Python call graph extraction

- Developed `stella-callgraph-python` to extract call graphs from Python projects using AST analysis.
- Implemented command-line interface with options for JSON output and verbose logging.
- Added framework detection to identify popular web frameworks and their entry points.
- Created an AST analyzer to traverse Python code and extract function definitions and calls.
- Included requirements.txt for project dependencies.

chore: add framework detection for Python projects

- Implemented framework detection logic to identify frameworks like Flask, FastAPI, Django, and others based on project files and import patterns.
- Enhanced the AST analyzer to recognize entry points based on decorators and function definitions.

tests/StellaOps.Router.Gateway.Tests/InMemoryRoutingStateTests.cs

@@ -0,0 +1,139 @@
+using FluentAssertions;
+using StellaOps.Router.Common.Enums;
+using StellaOps.Router.Common.Models;
+using StellaOps.Router.Gateway.State;
+using Xunit;
+
+namespace StellaOps.Router.Gateway.Tests;
+
+public sealed class InMemoryRoutingStateTests
+{
+    [Fact]
+    public void ResolveEndpoint_WhenExactMatch_ReturnsEndpointDescriptor()
+    {
+        var routingState = new InMemoryRoutingState();
+
+        var connection = CreateConnection("conn-1", "inventory", "1.0.0", region: "test");
+        connection.Endpoints[("GET", "/items")] = new EndpointDescriptor
+        {
+            ServiceName = "inventory",
+            Version = "1.0.0",
+            Method = "GET",
+            Path = "/items"
+        };
+
+        routingState.AddConnection(connection);
+
+        var resolved = routingState.ResolveEndpoint("GET", "/items");
+
+        resolved.Should().NotBeNull();
+        resolved!.ServiceName.Should().Be("inventory");
+        resolved.Version.Should().Be("1.0.0");
+        resolved.Method.Should().Be("GET");
+        resolved.Path.Should().Be("/items");
+    }
+
+    [Fact]
+    public void ResolveEndpoint_WhenTemplateMatch_ReturnsEndpointDescriptor()
+    {
+        var routingState = new InMemoryRoutingState();
+
+        var connection = CreateConnection("conn-1", "inventory", "1.0.0", region: "test");
+        connection.Endpoints[("GET", "/items/{sku}")] = new EndpointDescriptor
+        {
+            ServiceName = "inventory",
+            Version = "1.0.0",
+            Method = "GET",
+            Path = "/items/{sku}"
+        };
+
+        routingState.AddConnection(connection);
+
+        var resolved = routingState.ResolveEndpoint("GET", "/items/SKU-001");
+
+        resolved.Should().NotBeNull();
+        resolved!.Path.Should().Be("/items/{sku}");
+    }
+
+    [Fact]
+    public void RemoveConnection_RemovesEndpointsFromIndex()
+    {
+        var routingState = new InMemoryRoutingState();
+
+        var connection = CreateConnection("conn-1", "inventory", "1.0.0", region: "test");
+        connection.Endpoints[("GET", "/items")] = new EndpointDescriptor
+        {
+            ServiceName = "inventory",
+            Version = "1.0.0",
+            Method = "GET",
+            Path = "/items"
+        };
+
+        routingState.AddConnection(connection);
+        routingState.ResolveEndpoint("GET", "/items").Should().NotBeNull();
+
+        routingState.RemoveConnection("conn-1");
+
+        routingState.ResolveEndpoint("GET", "/items").Should().BeNull();
+        routingState.GetAllConnections().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void GetConnectionsFor_FiltersByServiceAndVersion()
+    {
+        var routingState = new InMemoryRoutingState();
+
+        var inventoryV1 = CreateConnection("inv-v1", "inventory", "1.0.0", region: "test");
+        inventoryV1.Endpoints[("GET", "/items")] = new EndpointDescriptor
+        {
+            ServiceName = "inventory",
+            Version = "1.0.0",
+            Method = "GET",
+            Path = "/items"
+        };
+
+        var inventoryV2 = CreateConnection("inv-v2", "inventory", "2.0.0", region: "test");
+        inventoryV2.Endpoints[("GET", "/items")] = new EndpointDescriptor
+        {
+            ServiceName = "inventory",
+            Version = "2.0.0",
+            Method = "GET",
+            Path = "/items"
+        };
+
+        routingState.AddConnection(inventoryV1);
+        routingState.AddConnection(inventoryV2);
+
+        var connections = routingState.GetConnectionsFor(
+            serviceName: "inventory",
+            version: "1.0.0",
+            method: "GET",
+            path: "/items");
+
+        connections.Should().HaveCount(1);
+        connections[0].ConnectionId.Should().Be("inv-v1");
+    }
+
+    private static ConnectionState CreateConnection(
+        string connectionId,
+        string serviceName,
+        string version,
+        string region)
+    {
+        return new ConnectionState
+        {
+            ConnectionId = connectionId,
+            Instance = new InstanceDescriptor
+            {
+                InstanceId = connectionId,
+                ServiceName = serviceName,
+                Version = version,
+                Region = region
+            },
+            Status = InstanceHealthStatus.Healthy,
+            LastHeartbeatUtc = DateTime.UtcNow,
+            TransportType = TransportType.InMemory
+        };
+    }
+}
+