feat(planning): author mission cascade (roadmap R-1, sprint 0001, feature F-1, mission)

[nolte]

Summary

Authors the planning cascade for nolte/workstation so it carries a spec-conformant project/mission.md, resolving Warning W1 from the 2026-06-02 portfolio audit (nolte/claude-shared#263) — the render placeholder for workstation clears once this lands and the inventory is re-rendered.

All content is grounded in the existing project/goals.md (outcomes O-1..O-4); nothing is invented.

Changes

• project/roadmap.md — add roadmap item R-1 "One-command provisioning of a complete developer workstation" (mvp: true, outcome O-1, target sprint 1).
• project/sprints/0001.md — open sprint 0001 with the value statement "a workstation-operator brings a fresh machine to a complete environment with one chezmoi init --apply".
• project/features/one-command-provisioning.md — feature F-1 decomposing R-1, three acceptance criteria, verifies_sprint_value: acceptance-1, manual consistency check recorded.
• project/mission.md — SMART mission with verifies_via: F-1:acceptance-1, mvp_status: defining, audiences from AUDIENCES.md.

Linked issues

Refs nolte/claude-shared#263

Testing

• All four frontmatter blocks parse as YAML; cross-references verified: roadmap R-1 ↔ sprint roadmap_items ↔ feature roadmap_item; sprint features ↔ feature id/sprint; mission verifies_via ↔ feature verifies_sprint_value/acceptance-1.

Risk / rollout notes

Low — planning documentation only; no code change. mvp_status starts at defining; acceptance criteria are manually verified (no automated provisioning test harness yet, noted in the feature's Risks).