Move the qt models to their own folder

Felt like the src folder was getting a bit crowded so move all the models to a folder named models.

src/models/completionproxymodel.h

@@ -0,0 +1,34 @@
+// SPDX-FileCopyrightText: 2022 Tobias Fella <fella@posteo.de>
+// SPDX-License-Identifier: LGPL-2.0-or-later
+
+#pragma once
+
+#include <QSortFilterProxyModel>
+
+class CompletionProxyModel : public QSortFilterProxyModel
+{
+    Q_OBJECT
+    Q_PROPERTY(int secondaryFilterRole READ secondaryFilterRole WRITE setSecondaryFilterRole NOTIFY secondaryFilterRoleChanged)
+    Q_PROPERTY(QString filterText READ filterText WRITE setFilterText NOTIFY filterTextChanged)
+
+public:
+    bool filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const override;
+    bool lessThan(const QModelIndex &source_left, const QModelIndex &source_right) const override;
+
+    int secondaryFilterRole() const;
+    void setSecondaryFilterRole(int role);
+
+    QString filterText() const;
+    void setFilterText(const QString &filterText);
+
+    void setFullText(const QString &fullText);
+
+Q_SIGNALS:
+    void secondaryFilterRoleChanged();
+    void filterTextChanged();
+
+private:
+    int m_secondaryFilterRole = -1;
+    QString m_filterText;
+    QString m_fullText;
+};