Set power level from userdetaildialog

Add the option to set powerlevel to userdetaildialog.

This is done by making the powerleveldialog into it's own file and using that.

implements network/neochat#570

src/neochatroom.h

@@ -153,6 +153,14 @@ public:
     [[nodiscard]] QString historyVisibility() const;
     void setHistoryVisibility(const QString &historyVisibilityRule);
 
+    /**
+     * @brief Get the power level for the given user ID in the room.
+     *
+     * Returns the default value for a user in the room if they have no escalated
+     * privileges or if they are not a member so membership should be known before using.
+     */
+    Q_INVOKABLE [[nodiscard]] int getUserPowerLevel(const QString &userId) const;
+
     Q_INVOKABLE void setUserPowerLevel(const QString &userID, const int &powerLevel);
 
     [[nodiscard]] int powerLevel(const QString &eventName, const bool &isStateEvent = false) const;