ck v2.0.0 — deterministic script architecture

ck v1.3.0 — performance fixes, release automation, template cleanup

docs: v1.2.0 — update README, CHANGELOG, CONTRIBUTING, sync SKILL.md

- README: document /ck:list (replaces /ck:status), /ck:info,
  number-based selection, auto-detect init, PATH/REPO in briefing,
  updated example briefing box and portfolio table; bump badge to 1.2.0
- CHANGELOG: add [1.2.0] entry with all changes since v1.1.0
- CONTRIBUTING: replace /ck:status → /ck:list, add /ck:info to test cmds
- SKILL.md: sync installed version (141 bytes newer) to repo

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs: bump version badge to v1.1.0