feat: error hint for non sustech email user

import { type RequestEvent } from '@sveltejs/kit';

import { error, type RequestEvent } from '@sveltejs/kit';

import { OAuth2RequestError } from 'oslo/oauth2';

import z from "zod"

import z, { ZodError } from "zod"

import oauth2Client, { credentials } from '$lib/server/auth/sustech-cloud';

import { db } from '$lib/server/db';

	} catch (e) {

		log.error(e);

		// the specific error message depends on the provider

		if (e instanceof ZodError) {

			error(400, { message: 'We could not infer your sustech ID from your email. Please contact the admin for help.' })

		}

		if (e instanceof OAuth2RequestError) {

			// invalid code

			log.error(e.request.url);