Figure out updates thread flow for fandom coder

[essential-randomness]

Problem

We need to communicate updates to the BobaBoard software to the new Fandom Coders Realm

Current status

These updates are currently communicated to v0 through a thread, which allows users to comment on them. The latest update is then surfaced to the main page as part of a subscription to the +release category in the specific thread. Updates to the subscription also trigger Discord webhooks that update both the v0 and volunteers server.

Long-term solution

We have discussed potentially sharing the updates thread across Realms (or even the full !bobaland board). But this would require too many architectural decisions for the 6/9 launch, and is better left at another time.

Stopgap solution

Expand our current thread-updates webhook solution to surface the contribution content upon update to the v0 board, then use Pipedream to crosspost that content to a pre-determined thread in fandom coders.

• [x] Update subscription webhook to include full content
• [ ] Create BobaBoard users with Fandom Coders-posting privileges and a specific role for updates.
• [x] Ensure Pipedream can log in as the "updates bot" and post to Boba
• [x] Write Pipedream code to do the automated crosspost.

[essential-randomness]

Managed to extremely hack together making a post when a webhook is triggered in pipedream:

[essential-randomness]

Server changes: https://github.com/essential-randomness/bobaserver/pull/69