(feat): improve notification and appeal system

Goal:

Meet requirements of Santa Clara Principles - https://newamericadotorg.s3.amazonaws.com/documents/Santa_Clara_Principles.pdf

Specs:

All users should receive in-app notification when a piece of content, or their channel, receives any type of moderation. All users should be able to view these actions in the Reported Content section of their settings console.

Notification Triggers:

• Content marked explicit = in-app notification and listed in reported content console
• Channel marked explicit = in-app notification and listed in reported content console
• Boost rejected = in-app notification and listed in reported content console
• Channel marked as spam = in-app notification and listed in reported content console
• Channel banned = email notification

All moderation notifications should contain:

• sufficient information to identify content in violation
• specific clause in terms that was violated
• how the content was flagged and actioned on
• clear explanation of how to appeal the decision

Appeal process:

• reviewed by different people than who made the original decision
• grant user opportunity to provide additional information for review of appeal
• notification of the results of the appeal so user may understand decision