[Feature Request] Allow a user to connect their Discord account to their Portal account

[stevenmqnguyen]

Overview

Set up the groundwork for future discord integration features. This groundwork includes grabbing user metadata, such as snowflake, username, and discriminator, from discord,

A user must first connect a Discord account. On each sign-in afterward, we need to fetch the user's metadata from Discord including their snowflake. This is done by using the access token in the accounts collection to send an api call to Discord.

Tasks

• Add Discord Auth URL with identify, email, guilds scope to NextAuth Discord provider options
• Get user metadata from Discord, including snowflake, username, discriminator
• Verify user is in acm server
• Add verified role
• Document

Supplemental Information

• NextAuth Discord Provider Options Docs
• portal v1 getting user metadata
• portal v1 discord features

[ReshmiCode]

ACM Members should get a members-only role on the Discord added to them and that role should be removed 2 semesters after receiving it (unless they continue on as a member). For our past members last semester, we just have their names and can get their emails. Members are people in any of ACM's programs, officers, and those who attend 5+ events.
This will allow us to make a members-only channel on the Discord which is the end goal.

[NickBurnett]

CC @ez314 (will ping him in discord)

[harshasrikara]

Old Portal Implementation
Old Portal Backend Implementation

Just adding these links to issue for quick reference