Update ban history formatting to include clearer unban details

Modified the history format service to display 'Unbanned by [user]' instead of just the user's name. This provides more explicit context for removed punishments in the UI.

frontend/src/app/bans/history-format.service.ts

@@ -32,7 +32,7 @@ export class HistoryFormatService {
   public getExpiredTime(entry: PunishmentHistory): string {
     let suffix: string = '';
     if (entry.removedBy !== null && entry.removedBy !== undefined) {
-      suffix = '(' + entry.removedBy + ')';
+      suffix = '(Unbanned by ' + entry.removedBy + ')';
     }
     if (entry.expiryTime <= 0) {
       return "Permanent " + this.getType(entry) + " " + suffix;