Release v0.2.1: support remote input, safe updates and high-DPI windows

src/update.h

@@ -0,0 +1,14 @@
+#pragma once
+#include "platform.h"
+namespace ks
+{
+inline constexpr wchar_t AppVersion[] = L"0.2.1";
+inline constexpr UINT UpdateMessage = WM_APP + 7;
+struct UpdateResult
+{
+    std::wstring state, version, error;
+    bool interactive{}, install{};
+};
+UpdateResult runUpdate(bool install, const std::wstring &expectedVersion);
+void confirmUpdatedStartup(const std::wstring &eventName);
+}