v0.4.0

Context discipline release.

• Added review-project-history for onboarding, prior-decision research, logs, archives, and old-plan review.
• Changed load-project-context to load compact active docs by default and search history only when needed.
• Changed maintain-project-docs to keep active docs small, prefer atomic decision records, and treat separate acceptance criteria as optional.
• Added spec.md, operations.md, and decision-record.md templates.
• Updated templates so implementation status is a current snapshot rather than a verification diary.
• Added an auditable no-doc-change escape hatch: Docs unchanged by design: <reason>.