feat: use discord_id from discord sso for role grant (#6326)

* feat: properly use labrinth's linked discord accts sso for discord bot

* Update email for fixture user in SQL insert

Signed-off-by: Calum H. <calum@modrinth.com>

* fix: rev changes

* fix: copy on email

* fix: lint

* fix: rev

* fix: lint

---------

Signed-off-by: Calum H. <calum@modrinth.com>

apps/frontend/src/pages/discord/link.vue

@@ -0,0 +1,62 @@
+<script setup lang="ts">
+import { injectModrinthClient } from '@modrinth/ui'
+
+import { getAuthUrl } from '~/composables/auth.js'
+
+definePageMeta({
+	layout: 'empty',
+	middleware: 'auth',
+})
+
+const route = useRoute()
+const auth = await useAuth()
+const client = injectModrinthClient()
+const error = ref<unknown>(null)
+const isLinkedCallback = computed(() => route.query.callback === 'linked')
+
+onMounted(async () => {
+	if (isLinkedCallback.value) return
+
+	try {
+		if (!auth.value.user?.auth_providers?.includes('discord')) {
+			window.location.href = `${getAuthUrl('discord', '/discord/link')}&token=${auth.value.token}`
+			return
+		}
+
+		const res = await client.labrinth.auth_internal.createDiscordCommunityLink()
+		window.location.href = res.url
+	} catch (err) {
+		error.value = err
+	}
+})
+</script>
+
+<template>
+	<section class="discord-link-container universal-card">
+		<h1>{{ isLinkedCallback ? 'Modrinth account linked' : 'Linking Discord' }}</h1>
+		<p v-if="isLinkedCallback">Your Modrinth account has been linked to the Discord server.</p>
+		<p v-else-if="!error">Connecting your Modrinth account to the Discord server...</p>
+		<p v-else>Discord linking failed. Please try again later.</p>
+	</section>
+</template>
+
+<style scoped>
+.discord-link-container {
+	width: 26rem;
+	max-width: calc(100% - 2rem);
+	margin: 1rem auto;
+	display: flex;
+	flex-direction: column;
+	gap: 2rem;
+}
+
+.discord-link-container h1 {
+	font-size: var(--font-size-xl);
+	margin: 0 0 -1rem 0;
+	color: var(--color-contrast);
+}
+
+.discord-link-container p {
+	margin: 0;
+}
+</style>