Replace db query with simple in-memory check of if account already exists.

src/commands/management.rs

@@ -34,7 +34,7 @@ impl Command for RegisterCommand {
     }
 
     async fn execute(&self, ctx: &Context<'_>) -> ExecutionResult {
-        if let Some(_) = ctx.db.get_user(ctx.username).await? {
+        if ctx.account.is_registered() {
             return Err(ExecutionError(BotError::AccountAlreadyExists));
         }
 
@@ -46,6 +46,7 @@ impl Command for RegisterCommand {
         };
 
         ctx.db.upsert_user(&user).await?;
+
         Execution::success(format!(
             "User account {} registered for bot commands.",
             ctx.username

src/models.rs

@@ -42,6 +42,11 @@ pub enum Account {
 }
 
 impl Account {
+    /// Whether or not this account is a registered user account.
+    pub fn is_registered(&self) -> bool {
+        matches!(self, Self::Registered(_))
+    }
+
     /// Gets the account status. For registered users, this is their
     /// actual account status (fully registered or awaiting
     /// activation). For transient users, this is