docs(work): close work-system-v1 epic

docs/work/work-system-v1/_epic.md

@@ -3,7 +3,7 @@ id: work-system-v1
 prd: null
 title: Work system v1 (MVP) — state tracking + pnpm work CLI
 type: epic
-status: in-progress
+status: done
 features: [scripts]
 created: 2026-05-13
 ---
@@ -25,4 +25,4 @@ work?" and "where are we?" — without scanning every story file by hand.
 - Pre-commit hooks (the state file is rebuilt manually for now)
 
 ## Stories
-- [ ] [01 — State builder + CLI](01-state-builder-and-cli/_story.md)
+- [x] [01 — State builder + CLI](01-state-builder-and-cli/_story.md)