Force `cl.exe` to parse Odin source as utf-8.

build.bat

@@ -48,6 +48,9 @@ if "%2" == "1" (
 set odin_version_raw="dev-%curr_year%-%curr_month%"
 
 set compiler_flags= -nologo -Oi -TP -fp:precise -Gm- -MP -FC -EHsc- -GR- -GF
+rem Parse source code as utf-8 even on shift-jis and other codepages
+rem See https://learn.microsoft.com/en-us/cpp/build/reference/utf-8-set-source-and-executable-character-sets-to-utf-8?view=msvc-170
+set compiler_flags= %compiler_flags% /utf-8
 set compiler_defines= -DODIN_VERSION_RAW=\"%odin_version_raw%\"
 
 if not exist .git\ goto skip_git_hash

src/ucg/ucg.c

@@ -1,4 +1,4 @@
-/*
+/*
  * SPDX-FileCopyrightText: (c) 2024 Feoramund
  * SPDX-License-Identifier: BSD-3-Clause
  */