sessions

Describe the bug

Currently there is no easy way to throw errors inside loaders/actions. We should probably come up with an easy to use solution.

I have something like the following in my head:

<script context="module" ssr>
  import {  NotFoundError, HttpError } from "svemix/errors"
  export const loader = () => {
    throw new NotFoundError("User not found").
    throw n

Implement Message.InspectMsg and suitable overrides. This function should be invoked when a message is sent, but only when a debug flag is enabled in a lab load. Its purpose is to verify that the message

• belongs to a valid protocol
• matches its PSM's protocol (if sent by a PSM)
• has a valid signal for its protocol
• contains all parameters that are mandatory for its signal
• contains