runtime: set 'cpoptions' for line-continuation in various runtime files

closes: #17121

Signed-off-by: Eisuke Kawashima <e-kwsm@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/syntax/tutor.vim b/runtime/syntax/tutor.vim
index 83ca547..7d0cd31 100644
--- a/runtime/syntax/tutor.vim
+++ b/runtime/syntax/tutor.vim
@@ -1,7 +1,14 @@
+" Language:	Vim Tutor
+" Maintainer:	Vim Project
+" Last Change:	2025 Apr 16
+
 if exists("b:current_syntax")
     finish
 endif
 
+let s:cpo_save = &cpo
+set cpo&vim
+
 syn include @VIM syntax/vim.vim
 unlet b:current_syntax
 syn include @TUTORSHELL syntax/sh.vim
@@ -75,3 +82,5 @@
 hi def link tutorShellPrompt Delimiter
 
 let b:current_syntax = "tutor"
+let &cpo = s:cpo_save
+unlet s:cpo_save