Update SOPs for mature-project ticket pattern

todo-mature-project-sop-updates Doc

todo done

Update SOPs for mature-project ticket pattern

As projects mature, not all work needs plan lineage. Phases are for foundational/architectural work. Improvements, features, and bugs on mature projects can be board tickets with Forgejo issues — no phase note needed. Five docs need updates to reflect this evolved practice:
  • convention-todo-lifecycle (medium) — Graduation can mean "Forgejo issue on board," not just "phase in plan." Distinguish greenfield (→ phase) from mature (→ ticket).
  • agent-spawn-conventions (small) — Reword "No plan, no agent" axiom headline to match the actual rule (plan, TODO, or project slug).
  • sop-board-workflow (small) — Triage step 3: differentiate scoping by item_type (phase needs phase note, issue needs acceptance criteria, todo needs clear title).
  • template-ticket (small) — Lifecycle: add mature-project arrival path (direct issue/todo without plan parentage).
  • template-phase (small) — Add "When to Use" decision gate (architecture change? cross-repo? new capability?).
Discovered: 2026-03-15, during F12/F13 scoping session. The practice already works — the docs just haven't caught up.