feat: add keyboard focus management for plugin surfaces

1. Added setKeyboardFocus method to PluginSurface class to handle
keyboard focus via Wayland seat
2. Exposed the method as Q_INVOKABLE for QML access
3. Implemented focus handling in ShellSurfaceItemProxy when hovered
4. Includes necessary QWaylandSeat header for keyboard focus management
5. This ensures proper keyboard input handling when interacting with
plugin surfaces

feat: 为插件表面添加键盘焦点管理

1. 在 PluginSurface 类中添加 setKeyboardFocus 方法，通过 Wayland seat 处
理键盘焦点
2. 将方法暴露为 Q_INVOKABLE 以便 QML 访问
3. 在 ShellSurfaceItemProxy 中实现悬停时的焦点处理
4. 包含必要的 QWaylandSeat 头文件用于键盘焦点管理
5. 确保与插件表面交互时能正确处理键盘输入

Pms: BUG-312795

Author: wjyrich

panels/dock/pluginmanagerextension.cpp

@@ -252,6 +252,14 @@ void PluginSurface::setGlobalPos(const QPoint &pos)
     send_raw_global_pos(p.x(), p.y());
 }
 
+void PluginSurface::setKeyboardFocus() 
+{
+    QWaylandCompositor *compositor = surface()->compositor();
+    if (QWaylandSeat *seat = compositor->defaultSeat()) {
+        seat->setKeyboardFocus(surface());
+    }
+}
+
 void PluginSurface::plugin_source_size(Resource *resource, int32_t width, int32_t height)
 {
     Q_UNUSED(resource);

panels/dock/pluginmanagerextension_p.h

@@ -9,6 +9,8 @@
 #include <QtWaylandCompositor/QWaylandCompositor>
 #include <QtWaylandCompositor/QWaylandSurface>
 #include <QtWaylandCompositor/QWaylandResource>
+#include <QtWaylandCompositor/QWaylandSeat>
+
 #include <cstdint>
 
 #include "qwayland-server-fractional-scale-v1.h"
@@ -161,7 +163,8 @@ class PluginSurface : public QWaylandShellSurfaceTemplate<PluginSurface>, public
 
     Q_INVOKABLE void updatePluginGeometry(const QRect &geometry);
     Q_INVOKABLE void setGlobalPos(const QPoint &pos);
-
+    Q_INVOKABLE void setKeyboardFocus();
+    
     int margins() const;
     void setMargins(int newMargins);
 

panels/dock/tray/ShellSurfaceItemProxy.qml

@@ -38,6 +38,12 @@ Item {
 
         HoverHandler {
             id: hoverHandler
+            onHoveredChanged: {
+                if (hovered && root.shellSurface) {
+                    console.log("Calling setKeyboardFocus on shellSurface")
+                    shellSurface.setKeyboardFocus()
+                }
+            }
         }
         TapHandler {
             id: tapHandler