Sim GUI: Support High DPI monitors

Add user setting for scaling on top of DPI scaling.
Add user setting for visual style (light/dark/normal).
Save window position, size, maximized state, scale, and style to ini file.

simulation/halsim_gui/src/main/native/cpp/EncoderGui.cpp

@@ -54,7 +54,7 @@ static void EncodersWriteAll(ImGuiContext* ctx, ImGuiSettingsHandler* handler,
 static void DisplayEncoders() {
   bool hasAny = false;
   static int numEncoder = HAL_GetNumEncoders();
-  ImGui::PushItemWidth(100);
+  ImGui::PushItemWidth(ImGui::GetFontSize() * 8);
   for (int i = 0; i < numEncoder; ++i) {
     if (HALSIM_GetEncoderInitialized(i)) {
       hasAny = true;