fix: relative path (#2023)

lua/avante/llm_tools/helpers.lua

@@ -13,9 +13,8 @@ M.confirm_popup = nil
 ---@param rel_path string
 ---@return string
 function M.get_abs_path(rel_path)
-  if Path:new(rel_path):is_absolute() then return rel_path end
   local project_root = Utils.get_project_root()
-  local p = tostring(Path:new(project_root):joinpath(rel_path):absolute())
+  local p = Utils.join_paths(project_root, rel_path)
   if p:sub(-2) == "/." then p = p:sub(1, -3) end
   return p
 end