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/paper-search-tools-paper-search-usage/SKILL.md

@@ -0,0 +1,27 @@
+---
+name: paper-search-usage
+description: This skill should be used when user asks to "search for papers", "find research papers", "search arXiv", "search PubMed", "find academic papers", "search IEEE", "search Scopus", or "look up scientific literature".
+---
+
+# Paper Search MCP
+
+Search academic papers across multiple platforms.
+
+## Supported Platforms
+
+- arXiv (preprints)
+- PubMed (biomedical)
+- IEEE Xplore (engineering)
+- Scopus (multidisciplinary)
+- ACM Digital Library (computer science)
+- Semantic Scholar (AI-powered)
+
+## Usage
+
+Use `mcp__paper-search__*` tools to search papers by keywords, authors, or topics.
+
+## Best Practices
+
+- Start with broad searches, then narrow down
+- Use platform-specific searches for domain-specific papers
+- Combine multiple sources for comprehensive literature reviews