v0.18.3

[0.18.3] - 2026-05-12

Added

• Added a Librarian Learning stage that runs after Planner in learning-enabled
  modes, checks Planner output against local and remote skill indexes, and
  installs up to eight relevant uninstalled remote optional skills into the
  workspace.
• Added shipped-skill lint regression coverage so every packaged SKILL.md
  asset must satisfy the current skill package contract.

Changed

• Curator guidance now permits safe format-only migration of a touched
  workspace-installed skill when an evidence-backed behavior patch is already
  being applied and the current linter reports package-shape drift.

Fixed

• Migrated the shipped marathon-qa-audit skill to the current required
  section contract so it passes the packaged skill linter.