Add function to prove ada/Spark code

lua/ada_mode.lua

@@ -3,11 +3,22 @@ if vim == nil then
 	local vim = {}
 end
 
+-- @name Prove
+-- @param
+-- @short Run gnatprove
+function Prove()
+	vim.cmd("new")
+	local run_cmd = { "alr gnatprove" }
+	vim.api.nvim_buf_set_lines(0, 0, -1, false, run_cmd)
+	vim.cmd(":%!bash")
+end
+
 -- @name setup_ada
 -- @param
 -- @short Verify installation of ada tools or install them.
 local function setup_ada()
 	vim.keymap.set("n", "<leader>cb", ":!gnatpp %<cr>")
+	vim.keymap.set("n", "<leader>pp", ":lua Prove()<cr>")
 	vim.opt.tabstop = 3
 	vim.opt.shiftwidth = 3
 end