chore: clean up repo for public release

- Remove BMAD framework, IDE configs, dev screenshots, test files,
  internal docs, and backup files
- Rename keep-notes/ to memento-note/
- Update all references from keep-notes to memento-note
- Add Apache 2.0 license with Commons Clause (non-commercial restriction)
- Add clean .gitignore and .env.docker.example

.agent/skills/bmad-brainstorming/template.md

@@ -1,15 +0,0 @@
----
-stepsCompleted: []
-inputDocuments: []
-session_topic: ''
-session_goals: ''
-selected_approach: ''
-techniques_used: []
-ideas_generated: []
-context_file: ''
----
-
-# Brainstorming Session Results
-
-**Facilitator:** {{user_name}}
-**Date:** {{date}}