feat(input): add host input remapping

Add compact keyboard and mouse mapping with analog-stick defaults and integrate a global remapping editor into the Qt launcher.

Based on the host input remapping work from PR #109.

Co-authored-by: DistantMyth <thetarun3@gmail.com>

src/launcher/include/inputMappingDialog.h

@@ -0,0 +1,31 @@
+#ifndef LAUNCHER_INCLUDE_INPUT_MAPPING_DIALOG_H_
+#define LAUNCHER_INCLUDE_INPUT_MAPPING_DIALOG_H_
+
+#include <QDialog>
+#include <QStringList>
+
+class QPushButton;
+class QTreeWidget;
+class QTreeWidgetItem;
+class QWidget;
+
+class InputMappingDialog final: public QDialog {
+public:
+	explicit InputMappingDialog(const QStringList& mapping, QWidget* parent = nullptr);
+
+	[[nodiscard]] QStringList Mapping() const;
+
+private:
+	void ChangeBinding();
+	void ClearBinding();
+	void RestoreDefaults();
+	void SetBinding(QTreeWidgetItem* item, const QString& binding);
+	void UpdateButtons();
+
+	QTreeWidget* m_bindings      = nullptr;
+	QPushButton* m_change_button = nullptr;
+	QPushButton* m_clear_button  = nullptr;
+	bool         m_customized    = false;
+};
+
+#endif /* LAUNCHER_INCLUDE_INPUT_MAPPING_DIALOG_H_ */