gui: add right-click context menu with Kill action for sessions

- Add killSession(sessionId) Q_INVOKABLE to Ollie9pClient
- Accept right button in session tree MouseArea
- Context menu with Kill option on right-click
- MenuItem resolves session ID via parent chain

gui/main.qml

@@ -533,9 +533,15 @@ ApplicationWindow {
 
                     MouseArea {
                         anchors.fill: parent
-                        acceptedButtons: Qt.LeftButton
+                        acceptedButtons: Qt.LeftButton | Qt.RightButton
                         hoverEnabled: false
                         onClicked: {
+                            if (mouse.button === Qt.RightButton) {
+                                if (type === "session") {
+                                    sessionCtxMenu.popup()
+                                }
+                                return
+                            }
                             if (renamingIndex >= 0) return
                             if (type === "session") {
                                 toggleExpand(parent.modelIndex)
@@ -548,6 +554,20 @@ ApplicationWindow {
                                 startRename(parent.modelIndex)
                             }
                         }
+
+                        Menu {
+                            id: sessionCtxMenu
+                            MenuItem {
+                                text: "Kill"
+                                icon.color: "#f44336"
+                                onClicked: {
+                                    var item = sessionTreeModel.get(parent.parent.parent.modelIndex)
+                                    if (item && item.type === "session")
+                                        ollie.killSession(item.id)
+                                    ollie.refreshSessions()
+                                }
+                            }
+                        }
                     }
 
                     contentItem: RowLayout {

gui/ollie9pclient.cpp

@@ -160,6 +160,21 @@ bool Ollie9pClient::kill()
     return proc.exitCode() == 0;
 }
 
+bool Ollie9pClient::killSession(const QString &sessionId)
+{
+    if (sessionId.isEmpty()) return false;
+    QStringList agents = getAgents(sessionId);
+    if (agents.isEmpty()) return false;
+    QString path = "session/" + sessionId + "/agent/" + agents.first() + "/ctl";
+    QProcess proc;
+    proc.start(ninepBin(), {"-a", serverAddr(), "write", path});
+    proc.waitForStarted(3000);
+    proc.write("kill");
+    proc.closeWriteChannel();
+    proc.waitForFinished(3000);
+    return proc.exitCode() == 0;
+}
+
 QString Ollie9pClient::getConfig()
 {
     if (m_activeSessionId.isEmpty()) return {};

gui/ollie9pclient.h

@@ -57,6 +57,7 @@ public:
     Q_INVOKABLE bool submit(const QString &prompt);
     Q_INVOKABLE bool interrupt();
     Q_INVOKABLE bool kill();
+    Q_INVOKABLE bool killSession(const QString &sessionId);
     Q_INVOKABLE QString getConfig();
     Q_INVOKABLE QStringList getAgents(const QString &sessionId);
     Q_INVOKABLE void setActiveAgentId(const QString &agentId);