Push Rule Model Rework

This is a significant rework of the handling of push rules. Rather than using a lot of boilerplate code for the default models `KeywordNotificationModel` has been converted to `PushRuleModel` and now handles all push rules.

The new model has the following features:
- Handles all push rules
- Has special handling for the names of default keywords (i.e. it still gives the same text as previously for showing in the settings menus)
- Push rules for blocking individuals or room overrides are still there but hidden so will be available for developer tools (to follow)
- Room specific keywords are now supported.

The notification settings pages have also been refactored to take advantage of the new models. Each section is now just a repeater with a filter for the rules that it should contain. The push rule delegate has now been cleaned up and uses required properties.

Implements network/neochat#574

src/models/keywordnotificationrulemodel.h

@@ -1,66 +0,0 @@
-// SPDX-FileCopyrightText: 2022 James Graham <james.h.graham@protonmail.com>
-// SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
-
-#pragma once
-
-#include <csapi/definitions/push_rule.h>
-
-#include <QAbstractListModel>
-
-/**
- * @class KeywordNotificationRuleModel
- *
- * This class defines the model for managing notification push rule keywords.
- */
-class KeywordNotificationRuleModel : public QAbstractListModel
-{
-    Q_OBJECT
-
-public:
-    /**
-     * @brief Defines the model roles.
-     */
-    enum EventRoles {
-        NameRole = Qt::DisplayRole, /**< The push rule keyword. */
-    };
-
-    KeywordNotificationRuleModel(QObject *parent = nullptr);
-
-    /**
-     * @brief Get the given role value at the given index.
-     *
-     * @sa QAbstractItemModel::data
-     */
-    [[nodiscard]] QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
-
-    /**
-     * @brief Number of rows in the model.
-     *
-     * @sa QAbstractItemModel::rowCount
-     */
-    [[nodiscard]] int rowCount(const QModelIndex &parent = QModelIndex()) const override;
-
-    /**
-     * @brief Returns a mapping from Role enum values to role names.
-     *
-     * @sa EventRoles, QAbstractItemModel::roleNames()
-     */
-    [[nodiscard]] QHash<int, QByteArray> roleNames() const override;
-
-    /**
-     * @brief Add a new keyword to the model.
-     */
-    Q_INVOKABLE void addKeyword(const QString &keyword);
-
-    /**
-     * @brief Remove a keyword from the model.
-     */
-    Q_INVOKABLE void removeKeywordAtIndex(int index);
-
-private Q_SLOTS:
-    void controllerConnectionChanged();
-    void updateNotificationRules(const QString &type);
-
-private:
-    QList<QString> m_notificationRules;
-};