refactor(cli)!: rename all skills and agents to consistent ce- prefix (#503)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

plugins/compound-engineering/skills/ce-polish-beta/SKILL.md

@@ -1,5 +1,5 @@
 ---
-name: ce:polish-beta
+name: ce-polish-beta
 description: "[BETA] Start the dev server, open the feature in a browser, and iterate on improvements together."
 disable-model-invocation: true
 argument-hint: "[PR number, branch name, or blank for current branch]"