feat(core): implement channel unreads model

closes #269

crates/core/database/src/models/mod.rs

@@ -1,6 +1,7 @@
 mod admin_migrations;
 mod bots;
 mod channel_invites;
+mod channel_unreads;
 mod channel_webhooks;
 mod channels;
 mod files;
@@ -13,6 +14,7 @@ mod users;
 pub use admin_migrations::*;
 pub use bots::*;
 pub use channel_invites::*;
+pub use channel_unreads::*;
 pub use channel_webhooks::*;
 pub use channels::*;
 pub use files::*;
@@ -31,6 +33,7 @@ pub trait AbstractDatabase:
     + bots::AbstractBots
     + channels::AbstractChannels
     + channel_invites::AbstractChannelInvites
+    + channel_unreads::AbstractChannelUnreads
     + channel_webhooks::AbstractWebhooks
     + files::AbstractAttachments
     + ratelimit_events::AbstractRatelimitEvents