Agent Skills: ring:applying-licenses

Applying or switching a repository's license (Apache 2.0, Elastic License v2, or Lerian Proprietary): rewrites the LICENSE file, updates Go/TS source headers, sets SPDX identifiers, and validates consistency after user confirmation. Use when asked to set, apply, or switch a license, or when scaffolding a service with no LICENSE. Skip when license, headers, and SPDX already match, or for non-code repos.