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/api/http/middleware/handler.go

@@ -0,0 +1,26 @@
+package middleware
+
+import "net/http"
+
+// HandlerFuncWithError is a http handler func which can return an error
+// the error should then get handled later on in the pipeline by an error handler
+// the error handler can be dependent on the interface standard (e.g. SCIM, Problem Details, ...)
+type HandlerFuncWithError = func(w http.ResponseWriter, r *http.Request) error
+
+// MiddlewareWithErrorFunc is a http middleware which can return an error
+// the error should then get handled later on in the pipeline by an error handler
+// the error handler can be dependent on the interface standard (e.g. SCIM, Problem Details, ...)
+type MiddlewareWithErrorFunc = func(HandlerFuncWithError) HandlerFuncWithError
+
+// ErrorHandlerFunc handles errors and returns a regular http handler
+type ErrorHandlerFunc = func(HandlerFuncWithError) http.Handler
+
+func ChainedWithErrorHandler(errorHandler ErrorHandlerFunc, middlewares ...MiddlewareWithErrorFunc) func(HandlerFuncWithError) http.Handler {
+	return func(next HandlerFuncWithError) http.Handler {
+		for i := len(middlewares) - 1; i >= 0; i-- {
+			next = middlewares[i](next)
+		}
+
+		return errorHandler(next)
+	}
+}