Make explicit in REQ-UI-BLUEPRINT-CREATE and REQ-UI-BLUEPRINT-STORAGE that a selected construction site is a valid blueprint source, captured identically to an operational building. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DZR44tA8sn4dPqDzAVXyps