Add .NET 8.0 C# port of OpenV2G EXI codec

- Port core EXI encoding/decoding functionality to C#
- Implement V2G protocol parsing and analysis
- Add simplified decoder/encoder for roundtrip testing
- Create comprehensive error handling with EXI exceptions
- Support both byte array and file stream operations
- Include packet structure analysis for V2GTP data
- Successfully builds and runs basic functionality tests

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

csharp/dotnet/bin/Debug/net6.0/V2GDecoderNet.deps.json

@@ -0,0 +1,23 @@
+{
+  "runtimeTarget": {
+    "name": ".NETCoreApp,Version=v6.0",
+    "signature": ""
+  },
+  "compilationOptions": {},
+  "targets": {
+    ".NETCoreApp,Version=v6.0": {
+      "V2GDecoderNet/1.0.0": {
+        "runtime": {
+          "V2GDecoderNet.dll": {}
+        }
+      }
+    }
+  },
+  "libraries": {
+    "V2GDecoderNet/1.0.0": {
+      "type": "project",
+      "serviceable": false,
+      "sha512": ""
+    }
+  }
+}