Add platform shortcut manager implementations

Introduce platform-specific ShortcutManager implementations and refactor core API.

- Add native implementations for Linux (X11), macOS (Carbon/Carbon HotKey API), and Windows (RegisterHotKey) including accelerator parsing, registration/unregistration, and event monitoring/threads.
- Add stub implementations for Android, iOS, and OHOS to provide platform placeholders.
- Expose a PIMPL interface in shortcut_manager.h (Impl) and add EmitShortcutActivated() for platform backends to notify the manager.
- Update shortcut_manager.cpp to use the PIMPL idiom, switch mutex guards to std::unique_lock where unlocking/relocking is required, remove the internal default Impl, and add EmitShortcutActivated implementation.
- Update CMakeLists.txt to link the Carbon framework on Apple builds.

The change centralizes platform differences behind the Impl interface and implements full hotkey handling on major desktop platforms while providing no-op stubs for mobile/embedded platforms.

Author: lijy91

src/CMakeLists.txt

@@ -76,6 +76,7 @@ elseif (CMAKE_SYSTEM_NAME STREQUAL "Linux")
     target_link_libraries(nativeapi PUBLIC PkgConfig::GTK PkgConfig::X11 PkgConfig::XI PkgConfig::AYATANA_APPINDICATOR pthread)
 elseif(APPLE)
     target_link_libraries(nativeapi PUBLIC "-framework Cocoa")
+    target_link_libraries(nativeapi PUBLIC "-framework Carbon")
     target_compile_options(nativeapi PRIVATE "-x" "objective-c++")
 elseif(CMAKE_SYSTEM_NAME STREQUAL "OHOS")
     target_link_libraries(nativeapi PUBLIC hilog_ndk.z)

src/platform/android/shortcut_manager_android.cpp

@@ -0,0 +1,27 @@
+#include "../../shortcut_manager.h"
+
+namespace nativeapi {
+
+class ShortcutManagerImpl final : public ShortcutManager::Impl {
+ public:
+  explicit ShortcutManagerImpl(ShortcutManager* manager) : manager_(manager) {}
+  ~ShortcutManagerImpl() override = default;
+
+  bool IsSupported() override { return false; }
+  bool RegisterShortcut(const std::shared_ptr<Shortcut>& /*shortcut*/) override { return false; }
+  bool UnregisterShortcut(const std::shared_ptr<Shortcut>& /*shortcut*/) override { return false; }
+  void SetupEventMonitoring() override {}
+  void CleanupEventMonitoring() override {}
+
+ private:
+  ShortcutManager* manager_;
+};
+
+ShortcutManager::ShortcutManager()
+    : pimpl_(std::make_unique<ShortcutManagerImpl>(this)), next_shortcut_id_(1), enabled_(true) {}
+
+ShortcutManager::~ShortcutManager() {
+  UnregisterAll();
+}
+
+}  // namespace nativeapi

src/platform/ios/shortcut_manager_ios.mm

@@ -0,0 +1,27 @@
+#include "../../shortcut_manager.h"
+
+namespace nativeapi {
+
+class ShortcutManagerImpl final : public ShortcutManager::Impl {
+ public:
+  explicit ShortcutManagerImpl(ShortcutManager* manager) : manager_(manager) {}
+  ~ShortcutManagerImpl() override = default;
+
+  bool IsSupported() override { return false; }
+  bool RegisterShortcut(const std::shared_ptr<Shortcut>& /*shortcut*/) override { return false; }
+  bool UnregisterShortcut(const std::shared_ptr<Shortcut>& /*shortcut*/) override { return false; }
+  void SetupEventMonitoring() override {}
+  void CleanupEventMonitoring() override {}
+
+ private:
+  ShortcutManager* manager_;
+};
+
+ShortcutManager::ShortcutManager()
+    : pimpl_(std::make_unique<ShortcutManagerImpl>(this)), next_shortcut_id_(1), enabled_(true) {}
+
+ShortcutManager::~ShortcutManager() {
+  UnregisterAll();
+}
+
+}  // namespace nativeapi