E4.1.1 Exclude marker-block contents from the multiset check #69

Part of: readme --write cannot refresh the tagline after a description change (readme-shrink) (E4.1).

Task

Exclude marker-block contents from the multiset check

Subtasks

• Only for blocks the skill generated
• Keep the guard for everything outside markers

Definition of done

• Tests added or updated and CI green
• Docs updated when the command surface or output changes
• No private registry data, local paths or private repository names in fixtures or docs