runtime: decouple Open and Launch commands and gx mapping from netrw

closes: #16494
fixes: ##16486

Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/plugin/openPlugin.vim

@@ -0,0 +1,24 @@
+vim9script
+
+# Vim runtime support library
+#
+# Maintainer:   The Vim Project <https://github.com/vim/vim>
+# Last Change:  2025 Jan 24
+
+import autoload 'dist/vim9.vim'
+
+command -complete=shellcmd -nargs=1 Launch vim9.Launch(trim(<q-args>))
+command -complete=file -nargs=1 Open vim9.Open(trim(<q-args>))
+
+const no_gx = get(g:, "nogx", get(g:, "netrw_nogx", false))
+if !no_gx
+  if maparg('gx', 'n') == ""
+    const file = get(g:, 'netrw_gx', '<cfile>')
+    nnoremap <unique> gx <scriptcmd>vim9.Open(expand(file))<CR>
+  endif
+  if maparg('gx', 'x') == ""
+    xnoremap <unique> gx <scriptcmd>vim9.Open(getregion(getpos('v'), getpos('.'), { type: mode() })->join())<CR>
+  endif
+endif
+
+# vim: ts=8 sts=2 sw=2 et