feat(windows): SMTC integration

winmediacontrol.h

@@ -0,0 +1,42 @@
+// SPDX-FileCopyrightText: 2026 Gary Wang <opensource@blumia.net>
+//
+// SPDX-License-Identifier: MIT
+
+#pragma once
+
+#include <QObject>
+#include <QString>
+#include <QImage>
+
+class WinMediaControlPrivate;
+
+class WinMediaControl : public QObject
+{
+    Q_OBJECT
+
+public:
+    explicit WinMediaControl(QObject* parent = nullptr);
+    ~WinMediaControl();
+
+    void initialize(void* hwnd);
+    void shutdown();
+
+    void setMetadata(const QString& title, const QString& artist,
+                     const QString& album);
+    void setCoverArt(const QImage& coverArt);
+    void setPlaybackState(int state);
+    void setPosition(qint64 positionMs, qint64 durationMs);
+    void setControlsEnabled(bool play, bool pause, bool stop,
+                            bool next, bool previous);
+
+signals:
+    void playRequested();
+    void pauseRequested();
+    void stopRequested();
+    void nextRequested();
+    void previousRequested();
+    void seekRequested(qint64 positionMs);
+
+private:
+    WinMediaControlPrivate* d = nullptr;
+};