Mino chapter-07

Added

• Chapter 07 project Skills: discover only direct .agents/skills/<name>/SKILL.md
  files in the captured startup project. Parse YAML name/description with a pinned
  YAML parser; do not scan home-directory skills or preload bodies into instructions.
• Persist a sorted catalog once per session, including empty catalogs. Restore it
  on restart and /resume, retain it through /clear and compaction, and scan anew
  for /new. Sessions created by earlier releases initialize their catalog on first
  use. The skill instruction prefix stays stable; service-side cache hits are not
  guaranteed.
• Add skill_view with a strict name argument. Read the current complete file only
  for registered skills, without confirmation; save paired calls/results through the
  existing Agent loop. Bash remains separately approved with the existing limits.
• Confine skill reads to the captured project, reject unsafe/special files, and bound
  file, metadata, and catalog sizes. Missing directories are empty; malformed skills
  fail discovery. Skill text is task guidance and grants no tool authorization.

Changed

• Write history version 4 and read versions 1–4. The new session_skills record is
  synced before use. Earlier releases cannot read new records; preserve private
  backups before upgrading if rollback is needed.
• Extend the default SOUL with Skills guidance, preserving existing user SOUL files.