Add function to get jj diff for current buffer

lua/jj_mini_diff/init.lua

@@ -24,6 +24,21 @@ local function _define_signs()
   vim.fn.sign_define("JjDiffDelete", { text = "─", texthl = "JjDiffDelete", numhl = "JjDiffDelete" })
 end
 
+-- Get jj diff output for the current buffer
+local function _get_jj_diff_for_buffer()
+  local file_path = vim.api.nvim_buf_get_name(0)
+  if file_path == "" then
+    return nil, "Current buffer is not associated with a file."
+  end
+
+  -- Run 'jj diff' for the specific file
+  local diff_output, err = _run_jj_command({ "diff", "--color=never", file_path })
+  if err then
+    return nil, err
+  end
+  return diff_output
+end
+
 function M.setup(opts)
   opts = opts or {}
   _define_signs() -- Call to define signs