Version Partitioner

Split master requirements.md into subversions for sequential planning.

Harness discovery

See ../nextstage-harness/references/artifact-layout.md and ../nextstage-harness/references/harness-discovery.md. Read core-subversions rule from harness when present.

Scope

• Read only: master {product_root}/docs/versions/{version_san}/requirements.md
• Do not: generate tasks, execution-handoff, or re-run Gate 1
• Do not load product backend/frontend rules — structural partition only

Algorithm