chore: restructure llm plugin to be more coherent & fix various bugs in llm ui

Plugins/ZShell/Llm/message.hpp

@@ -10,13 +10,16 @@
 
 namespace ZShell::llm {
 
+class ChatSession;
+
 class ChatMessage : public QObject {
 	Q_OBJECT
 	QML_ELEMENT
-	QML_UNCREATABLE("Chat messages are created by the Chat singleton")
+	QML_UNCREATABLE("Chat messages are created by ChatMessageModel")
 
 	Q_PROPERTY(Role role READ role CONSTANT)
 	Q_PROPERTY(qint64 timestamp READ timestamp CONSTANT)
+	Q_PROPERTY(QString content READ content NOTIFY contentChanged)
 	Q_PROPERTY(
 		int generationCount READ generationCount NOTIFY generationsChanged)
 	Q_PROPERTY(
@@ -36,10 +39,16 @@ class ChatMessage : public QObject {
 	enum class Role : int { User = 0, Assistant };
 	Q_ENUM(Role)
 
-	explicit ChatMessage(Role role, qint64 timestamp, QObject* parent = nullptr);
+	ChatMessage(
+		ChatSession* session,
+		Role role,
+		qint64 timestamp,
+		QObject* parent = nullptr);
 
+	[[nodiscard]] ChatSession* session() const { return m_session; }
 	[[nodiscard]] Role role() const { return m_role; }
 	[[nodiscard]] qint64 timestamp() const { return m_timestamp; }
+	[[nodiscard]] QString content() const;
 	[[nodiscard]] int generationCount() const {
 		return static_cast<int>(m_generations.size());
 	}
@@ -68,7 +77,10 @@ class ChatMessage : public QObject {
 	ChatGeneration* appendGeneration(qint64 timestamp);
 	void removeGeneration(ChatGeneration* generation);
 
+	void setContent(const QString& value);
+
 	Q_SIGNALS:
+	void contentChanged();
 	void generationsChanged();
 	void activeGenerationChanged();
 	void attachmentsChanged();
@@ -76,8 +88,10 @@ class ChatMessage : public QObject {
 	private:
 	void setActiveInternal(int index);
 
+	ChatSession* m_session;
 	Role m_role;
 	qint64 m_timestamp;
+	QString m_content;
 	QList<ChatGeneration*> m_generations;
 	QList<Attachment*> m_attachments;
 	int m_active = -1;