Add dev scripts for mitmproxy debugging and fix JSON-RPC error responses

- Add dev-with-mitm.sh for TUI-based traffic inspection
- Add dev-with-mitmweb.sh for web UI-based traffic inspection
- Fix missing 'id' field in JSON-RPC error responses (required by spec)
- Migrate from zod-to-json-schema to Zod v4's native z.toJSONSchema()

The mitmproxy scripts help developers debug MCP traffic by running
the server through a reverse proxy that intercepts all client requests.

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

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

src/modules/mcp/handlers/shttp.ts

@@ -67,6 +67,7 @@ export async function handleStreamableHTTP(req: Request, res: Response) {
       });
       res.status(401).json({
         "jsonrpc": "2.0",
+        "id": null,
         "error": {
           "code": -32002,
           "message": "User ID required"
@@ -87,6 +88,7 @@ export async function handleStreamableHTTP(req: Request, res: Response) {
         });
         res.status(401).json({
           "jsonrpc": "2.0",
+          "id": null,
           "error": {
             "code": -32001,
             "message": "Session not found or access denied"
@@ -148,6 +150,7 @@ export async function handleStreamableHTTP(req: Request, res: Response) {
       });
       res.status(400).json({
         "jsonrpc": "2.0",
+        "id": null,
         "error": {
           "code": -32600,
           "message": "Invalid request method for existing session"
@@ -167,6 +170,7 @@ export async function handleStreamableHTTP(req: Request, res: Response) {
     if (!res.headersSent) {
       res.status(500).json({
         "jsonrpc": "2.0",
+        "id": null,
         "error": {
           "code": -32603,
           "message": "Internal error during request processing"