Windows: Add application manifest to set ActiveCodePage to UTF-8

This will set the process code page to UTF-8 on Windows 10 version 1903
or above, allowing Japanese file names to be handled correctly even if
the system locale is not Japanese.

src/win/resources.rc

@@ -2,6 +2,7 @@
 #include <afxres.h>
 #include "resources.h"
 
+CREATEPROCESS_MANIFEST_RESOURCE_ID RT_MANIFEST "xsystem35.exe.manifest"
 100 ICON DISCARDABLE "xsystem35.ico"
 
 // Note for game translators:

src/win/xsystem35.exe.manifest

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+  <application>
+    <windowsSettings>
+      <activeCodePage xmlns="http://schemas.microsoft.com/SMI/2019/WindowsSettings">UTF-8</activeCodePage>
+    </windowsSettings>
+  </application>
+</assembly>