Missing message types & DiscordMessage properties
Created by: uwx
Summary
There are several recently-added Message fields that the lib does not yet expose.
Details
As per the API documentation, the following message types are missing: USER_PREMIUM_GUILD_SUBSCRIPTION, USER_PREMIUM_GUILD_SUBSCRIPTION_TIER_1, USER_PREMIUM_GUILD_SUBSCRIPTION_TIER_2 and USER_PREMIUM_GUILD_SUBSCRIPTION_TIER_3. They should be added here:
The activity and application message properties are also not exposed, as per API.
In addition, Author is seemingly not correctly handled for webhooks (the API specifically notes that it might not be a valid user object, and I'm not sure what the lib does in this case)