nvim: Add FeMaco codecell edit mapping

Added mapping to quickly edit any code cell in FeMaco, an extra buffer
which brings lsp functionality and similar with it. Can be used as a
fallback if otter.nvim is not working for the buffer, or when working on
a buffer which otter.nvim does not understand.

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

@@ -203,8 +203,10 @@ return {
 		dependencies = {
 			"nvim-treesitter/nvim-treesitter",
 		},
+		keys = {
+			{ "<localleader>ce", ":FeMaco<cr>", desc = "edit codecell" },
+		},
 	},
-
 	-- MARKDOWN ONLY
 	-- Evaluate markdown code blocks
 	{