Add license text for go.sum to satisfy REUSE tool

Changes

1 changed files (+4/-0)

• go.sum.license (new)
  • @@ -0,0 +1,4 @@
    + Copyright 2025 Shota FUJI + SPDX-License-Identifier: 0BSD + + REUSE tool requires every file to be copyrighted and licensed, even auto-generated files.