add: user coins and transactions

crates/core/src/model/auth.rs

@@ -92,6 +92,9 @@ pub struct User {
     /// The time at which the user's ban will automatically expire.
     #[serde(default)]
     pub ban_expire: usize,
+    /// The number of coins the user has.
+    #[serde(default)]
+    pub coins: i32,
 }
 
 pub type UserConnections =
@@ -397,6 +400,7 @@ impl User {
             channel_mutes: Vec::new(),
             is_deactivated: false,
             ban_expire: 0,
+            coins: 0,
         }
     }