v0.3.0

The Crossmatrix hub: Junior ties CPM, FMECA, jevitate, tests and code
together in a committed .crossmatrix/ store (requires Crossmatrix 0.3.0).

Added

• junior matrix export and junior matrix sync: turn code, tests, jevitate
  jobs/personas/journeys, CPM deliverables and FMECA failure modes into
  Crossmatrix dimensions with content hashes; an unchanged re-sync is a no-op.
• junior matrix init: create the project's committed .crossmatrix/ store.
• The code map: junior matrix codemap init, junior matrix link (record
  the files a handoff changed against its feature), junior matrix files,
  junior matrix context (a contract context array) and
  junior matrix stale (links to re-confirm after changes).
• Crossmatrix as an npm companion with its agent skills.
• junior tools call uses the project's .crossmatrix/ store with
  Crossmatrix 0.3.0+ instead of replaying the model on every call.
• The Crossmatrix hub section in the manager skill.
• A slim README with reference documentation under docs/, and this changelog.

Published as @matthew-cochran/junior@0.3.0 (#30, #31, #32, #33).