nvim: Ensure FeMaCo newline in codefence injections

When formatting femaco buffers it would sometimes remove the newline
necessary at the end of code fences to have the (```) remain on its own
line. This attempts to fix it.

nvim/.config/nvim/lua/plugins/data_analysis.lua

@@ -227,8 +227,15 @@ return {
 		cmd = {
 			"FeMaco",
 		},
-		ft = { "markdown", "quarto" },
-		opts = {},
+		ft = { "markdown", "rmd", "quarto" },
+		opts = {
+			ensure_newline = function(base_ft)
+				if base_ft == "quarto" or base_ft == "markdown" then
+					return true
+				end
+				return false
+			end,
+		},
 		dependencies = {
 			"nvim-treesitter/nvim-treesitter",
 		},