Remove NormalizeContentType middleware workaround

The go-sdk bump (27f29c1) includes the proper fix upstream, making
the middleware unnecessary.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: IrynaKulakova

pkg/http/handler.go

@@ -127,7 +127,6 @@ func NewHTTPMcpHandler(
 
 func (h *Handler) RegisterMiddleware(r chi.Router) {
 	r.Use(
-		middleware.NormalizeContentType,
 		middleware.ExtractUserToken(h.oauthCfg),
 		middleware.WithRequestConfig,
 		middleware.WithMCPParse(),