feat: Add session layout

sources/Session/ConversationHistory.hpp

@@ -0,0 +1,49 @@
+// Copyright (C) 2024-2026 Petr Mironychev
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <LLMQore/ContentBlocks.hpp>
+
+#include <QObject>
+
+#include <memory>
+#include <vector>
+
+#include "Message.hpp"
+
+namespace QodeAssist {
+
+class ConversationHistory : public QObject
+{
+    Q_OBJECT
+    Q_DISABLE_COPY_MOVE(ConversationHistory)
+public:
+    explicit ConversationHistory(QObject *parent = nullptr);
+    ~ConversationHistory() override;
+
+    const std::vector<Message> &messages() const noexcept { return m_messages; }
+    int size() const noexcept { return static_cast<int>(m_messages.size()); }
+    bool isEmpty() const noexcept { return m_messages.empty(); }
+
+    void append(Message message);
+
+    void appendBlockToLast(std::unique_ptr<LLMQore::ContentBlock> block);
+
+    void appendTextDeltaToLast(const QString &delta);
+    void appendThinkingDeltaToLast(const QString &delta, const QString &signature = QString());
+
+    void clear();
+    void resetTo(int index);
+
+signals:
+    void messageAdded(int index);
+    void messageUpdated(int index);
+    void cleared();
+    void reset();
+
+private:
+    std::vector<Message> m_messages;
+};
+
+} // namespace QodeAssist