Add comprehensive skills, agents, commands collection

- Added 44 external skills from obra/superpowers, ui-ux-pro-max-skill, claude-codex-settings
- Added 8 autonomous agents (commit-creator, pr-creator, pr-reviewer, etc.)
- Added 23 slash commands for Git/GitHub, setup, and plugin development
- Added hooks for code formatting, notifications, and validation
- Added MCP configurations for Azure, GCloud, Supabase, MongoDB, etc.
- Added awesome-openclaw-skills registry (3,002 skills referenced)
- Updated comprehensive README with full documentation

Sources:
- github.com/obra/superpowers (14 skills)
- github.com/nextlevelbuilder/ui-ux-pro-max-skill (1 skill)
- github.com/fcakyon/claude-codex-settings (29 skills, 8 agents, 23 commands)
- github.com/VoltAgent/awesome-openclaw-skills (registry)
- skills.sh (reference)
- buildwithclaude.com (reference)

skills/external/github-dev-setup/SKILL.md

@@ -0,0 +1,32 @@
+---
+name: setup
+description: This skill should be used when the user asks "how to setup GitHub CLI", "configure gh", "gh auth not working", "GitHub CLI connection failed", "gh CLI error", or needs help with GitHub authentication.
+---
+
+# GitHub CLI Setup
+
+Configure `gh` CLI for GitHub access.
+
+## Quick Setup
+
+```bash
+gh auth login
+```
+
+Select: GitHub.com → HTTPS → Login with browser
+
+## Verify Authentication
+
+```bash
+gh auth status
+gh api user --jq '.login'
+```
+
+## Troubleshooting
+
+If `gh` commands fail:
+
+1. **Check authentication** - `gh auth status`
+2. **Re-login if needed** - `gh auth login`
+3. **Check scopes** - Ensure token has repo access
+4. **Update gh** - `brew upgrade gh` or equivalent