add context panel

app/gcompose/src/MainPanel.h

@@ -5,6 +5,11 @@
 
 class QSplitter;
 class ViewportPane;
+class ContextPanel;
+
+namespace uLib {
+    class ObjectsContext;
+}
 
 class MainPanel : public QWidget {
     Q_OBJECT
@@ -12,11 +17,19 @@ public:
     explicit MainPanel(QWidget* parent = nullptr);
     virtual ~MainPanel();
 
+    void setContext(uLib::ObjectsContext* context);
     ViewportPane* getFirstPane() const { return m_firstPane; }
 
+private slots:
+    void onOpen();
+    void onSave();
+    void onDarkTheme();
+    void onBrightTheme();
+
 private:
     QSplitter* m_rootSplitter;
     ViewportPane* m_firstPane;
+    ContextPanel* m_contextPanel;
 };
 
 #endif // MAINPANEL_H