feat: add GitHub Copilot support

- Add .github/prompts/ui-ux-pro-max.prompt.md for Copilot
- Add 'copilot' as new AI type in CLI
- Update detect utility to recognize .github folder
- Update CLAUDE.md sync rules with .github
- Update README with Copilot installation and usage
- Bump version to 1.2.0

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

CLAUDE.md

@@ -41,6 +41,7 @@ Available stacks: `html-tailwind` (default), `react`, `nextjs`, `vue`, `svelte`,
 
 .windsurf/workflows/              # Windsurf workflow copy
 .agent/workflows/ui-ux-pro-max/   # Generic agent workflow copy
+.github/prompts/                  # GitHub Copilot prompt
 .shared/ui-ux-pro-max/            # Shared data copy
 ```
 
@@ -51,8 +52,8 @@ The search engine uses BM25 ranking combined with regex matching. Domain auto-de
 When modifying files, keep all agent workflows in sync:
 
 - **Data & Scripts** (`data/`, `scripts/`): Copy changes to `.shared/ui-ux-pro-max/` and `cli/assets/.shared/ui-ux-pro-max/`
-- **SKILL.md**: Update corresponding files in `.agent/`, `.cursor/`, `.windsurf/`
-- **CLI assets**: Copy all skill folders to `cli/assets/` (`.claude/`, `.cursor/`, `.windsurf/`, `.agent/`, `.shared/`)
+- **SKILL.md**: Update corresponding files in `.agent/`, `.cursor/`, `.windsurf/`, `.github/prompts/`
+- **CLI assets**: Copy all skill folders to `cli/assets/` (`.claude/`, `.cursor/`, `.windsurf/`, `.agent/`, `.github/`, `.shared/`)
 
 ## Prerequisites