refactor: Restructure project into sources/tests layout and dissolve PluginLLMCore

sources/widgets/CustomInstructionsManager.hpp

@@ -0,0 +1,49 @@
+// Copyright (C) 2024-2026 Petr Mironychev
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Additional attribution terms under GPLv3 §7(b) apply — see LICENSE
+
+#pragma once
+
+#include <QObject>
+#include <QString>
+#include <QVector>
+
+namespace QodeAssist {
+
+struct CustomInstruction
+{
+    QString id;
+    QString name;
+    QString body;
+    bool isDefault = false;
+};
+
+class CustomInstructionsManager : public QObject
+{
+    Q_OBJECT
+
+public:
+    static CustomInstructionsManager &instance();
+
+    bool loadInstructions();
+    bool saveInstruction(const CustomInstruction &instruction);
+    bool deleteInstruction(const QString &id);
+    
+    QVector<CustomInstruction> instructions() const { return m_instructions; }
+    CustomInstruction getInstructionById(const QString &id) const;
+    
+signals:
+    void instructionsChanged();
+
+private:
+    explicit CustomInstructionsManager(QObject *parent = nullptr);
+    ~CustomInstructionsManager() override = default;
+    
+    QString getInstructionsDirectory() const;
+    bool ensureDirectoryExists() const;
+    
+    QVector<CustomInstruction> m_instructions;
+};
+
+} // namespace QodeAssist
+