diff --git a/.gsd/STATE.md b/.gsd/STATE.md
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-# GSD State
-
-**Active Milestone:** M003 — Worktree-Isolated Git Architecture
-**Active Slice:** None
-**Phase:** pre-planning
-
-## Milestone Registry
-- ✅ **M001:** Proactive Secret Management
-- ✅ **M002:** Browser Tools Performance & Intelligence
-- 🔄 **M003:** Worktree-Isolated Git Architecture
-
-## Recent Decisions
-- D027: Git isolation model — worktree-per-milestone (default for new projects)
-- D028: Slice merge strategy within worktree — --no-ff merge
-- D029: Milestone-to-main merge strategy — squash merge
-- D030: Failure handling philosophy — stop but self-heal
-- D031: Target user priority — vibe coder first
-
-## Blockers
-- None
-
-## Next Action
-Research and plan M003. Context and roadmap are written. Ready for auto-mode.
diff --git a/.gsd/milestones/M003/M003-META.json b/.gsd/milestones/M003/M003-META.json
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+{
+  "integrationBranch": "main"
+}