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/controller.h

@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include "models/pushrulemodel.h"
 #include <QObject>
 #include <QQuickItem>
 
@@ -50,6 +51,11 @@ class Controller : public QObject
      */
     Q_PROPERTY(Quotient::Connection *activeConnection READ activeConnection WRITE setActiveConnection NOTIFY activeConnectionChanged)
 
+    /**
+     * @brief The PushRuleModel that has the active connection's push rules.
+     */
+    Q_PROPERTY(PushRuleModel *pushRuleModel READ pushRuleModel CONSTANT)
+
     /**
      * @brief The row number in the accounts directory of the active connection.
      */
@@ -119,6 +125,8 @@ public:
     void setActiveConnection(Quotient::Connection *connection);
     [[nodiscard]] Quotient::Connection *activeConnection() const;
 
+    [[nodiscard]] PushRuleModel *pushRuleModel() const;
+
     /**
      * @brief Add a new connection to the account registry.
      */
@@ -236,6 +244,8 @@ private:
 
     bool hasWindowSystem() const;
 
+    QPointer<PushRuleModel> m_pushRuleModel;
+
 private Q_SLOTS:
     void invokeLogin();
     void showWindow();