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-brainstorm/references/universal-brainstorming.md

@@ -1,6 +1,6 @@
 # Universal Brainstorming Facilitator
 
-This file is loaded when ce:brainstorm detects a non-software task (Phase 0). It replaces the software-specific brainstorming phases with facilitation principles for any domain. Do not follow the software brainstorming workflow (Phases 0.2 through 4). Instead, absorb these principles and facilitate the brainstorm naturally.
+This file is loaded when ce-brainstorm detects a non-software task (Phase 0). It replaces the software-specific brainstorming phases with facilitation principles for any domain. Do not follow the software brainstorming workflow (Phases 0.2 through 4). Instead, absorb these principles and facilitate the brainstorm naturally.
 
 ---
 
@@ -49,7 +49,7 @@ When the conversation has enough material to narrow — reflect back what you've
 
 **Question:** "Brainstorm wrapped. What would you like to do next?"
 
-- **Create a plan** → hand off to `/ce:plan` with the decided goal and constraints
+- **Create a plan** → hand off to `/ce-plan` with the decided goal and constraints
 - **Save summary to disk** → write the summary as a markdown file in the current working directory
-- **Open in Proof (web app) — review and comment to iterate with the agent** → load the `proof` skill to open the doc in Every's Proof editor, iterate with the agent via comments, or copy a link to share with others
+- **Open in Proof (web app) — review and comment to iterate with the agent** → load the `ce-proof` skill to open the doc in Every's Proof editor, iterate with the agent via comments, or copy a link to share with others
 - **Done** → the conversation was the value, no artifact needed