home: vim: signtoggle: use lua autocommands

A nice next step would be to use actual lua callbacks instead of the
VimL command.

home/vim/plugin/signtoggle.vim

@@ -1,8 +1,22 @@
-augroup signtoggle
-    autocmd!
-    " Only show the sign column for the current focused buffer
-    autocmd BufEnter,FocusGained,WinEnter * set signcolumn=yes
-    autocmd BufLeave,FocusLost,WinLeave   * set signcolumn=no
-    " Disable the sign column in terminal
-    autocmd TermOpen * setlocal signcolumn=no
-augroup END
+lua << EOF
+local signtoggle = vim.api.nvim_create_augroup("signtoggle", { clear = true })
+
+-- Only show sign column for the currently focused buffer
+vim.api.nvim_create_autocmd({ "BufEnter", "FocusGained", "WinEnter" }, {
+    pattern = "*",
+    group = signtoggle,
+    command = "setlocal signcolumn=yes",
+})
+vim.api.nvim_create_autocmd({ "BufLeave", "FocusLost", "WinLeave" }, {
+    pattern = "*",
+    group = signtoggle,
+    command = "setlocal signcolumn=yes",
+})
+
+-- Never show the sign column in a terminal buffer
+vim.api.nvim_create_autocmd({ "TermOpen" }, {
+    pattern = "*",
+    group = signtoggle,
+    command = "setlocal signcolumn=no",
+})
+EOF