Slate v2 Roadmap Next-Move Closeout

Supporting plan. For current queue and roadmap truth, see master-roadmap.md.

Goal

• Remove the last stale "next move" sections that still pointed people back into old Phase 8 roadmap language.

Finding

• phase6-hardening.md still ended with "Current active move after that: Phase 8 package API shaping".
• cohesive-program-plan.md still had an Immediate Next Step section that told readers to run active work through Phase 8.

Patch

• Reframe those sections around the current read:
  • Phase 8/9/10 roadmap follow-on is landed historical work
  • default next work is implementation or shipping
  • further roadmap work is selective only when it changes the claim

Verification

• pnpm exec prettier --check /Users/zbeyens/git/plate-2/docs/slate-v2/archive/phase6-hardening.md /Users/zbeyens/git/plate-2/docs/slate-v2/archive/cohesive-program-plan.md /Users/zbeyens/git/plate-2/docs/plans/2026-04-07-slate-v2-roadmap-next-move-closeout.md
• grep confirms the stale Phase 8 next-move wording is gone from the target docs