feat: create user scim v2 endpoint (#9132)

# Which Problems Are Solved
- Adds infrastructure code (basic implementation, error handling,
middlewares, ...) to implement the SCIM v2 interface
- Adds support for the user create SCIM v2 endpoint

# How the Problems Are Solved
- Adds support for the user create SCIM v2 endpoint under `POST
/scim/v2/{orgID}/Users`

# Additional Context

Part of #8140

internal/zerrors/zerror.go

@@ -79,3 +79,8 @@ func (err *ZitadelError) As(target interface{}) bool {
 	reflect.Indirect(reflect.ValueOf(target)).Set(reflect.ValueOf(err))
 	return true
 }
+
+func IsZitadelError(err error) bool {
+	zitadelErr := new(ZitadelError)
+	return errors.As(err, &zitadelErr)
+}