runtime(squirrel): include squirrel ftplugin file

Comment spec found [here](https://squirrel-lang.org/squirreldoc/reference/language/lexical_structure.html#comments)

closes: #15172

Signed-off-by: Riley Bruins <ribru17@hotmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/ftplugin/squirrel.vim b/runtime/ftplugin/squirrel.vim
new file mode 100644
index 0000000..559be88
--- /dev/null
+++ b/runtime/ftplugin/squirrel.vim
@@ -0,0 +1,17 @@
+" Vim filetype plugin
+" Language:	Squirrel
+" Maintainer:	Riley Bruins <ribru17@gmail.com>
+" Last Change:	2024 Jul 06
+
+if exists('b:did_ftplugin')
+  finish
+endif
+let b:did_ftplugin = 1
+
+" Set 'comments' to format dashed lists in comments.
+" Also include ///, used for Doxygen.
+setlocal comments=sO:*\ -,mO:*\ \ ,exO:*/,s1:/*,mb:*,ex:*/,:///,://
+
+setlocal commentstring=//\ %s
+
+let b:undo_ftplugin = 'setl com< cms<'