runtime(proto): include filetype plugin for protobuf

closes: #16199

Signed-off-by: David Pedersen <limero@me.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/ftplugin/proto.vim

@@ -0,0 +1,18 @@
+" Vim filetype plugin
+" Language:	Protobuf
+" Maintainer:	David Pedersen <limero@me.com>
+" Last Change:	2024 Dec 09
+
+if exists('b:did_ftplugin')
+  finish
+endif
+let b:did_ftplugin = 1
+
+setlocal formatoptions-=t formatoptions+=croql
+
+setlocal comments=s1:/*,mb:*,ex:*/,://
+setlocal commentstring=//\ %s
+
+let b:undo_ftplugin = "setlocal formatoptions< comments< commentstring<"
+
+" vim: sw=2 sts=2 et