Remove all references to daemon keys from the codebase

app/Models/Subuser.php

@@ -99,14 +99,4 @@ class Subuser extends Model
     {
         return $this->hasMany(Permission::class);
     }
-
-    /**
-     * Return the key that belongs to this subuser for the server.
-     *
-     * @return \Illuminate\Database\Eloquent\Relations\HasOne
-     */
-    public function key()
-    {
-        return $this->hasOne(DaemonKey::class, 'server_id', 'server_id')->where('daemon_keys.user_id', '=', $this->user_id);
-    }
 }