Reorganize: Move all skills to skills/ folder

- Created skills/ directory
- Moved 272 skills to skills/ subfolder
- Kept agents/ at root level
- Kept installation scripts and docs at root level

Repository structure:
- skills/           - All 272 skills from skills.sh
- agents/           - Agent definitions
- *.sh, *.ps1       - Installation scripts
- README.md, etc.   - Documentation

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

skills/plugins/marketplaces/superpowers-marketplace/README.md

@@ -0,0 +1,96 @@
+# Superpowers Marketplace
+
+Curated Claude Code plugins for skills, workflows, and productivity tools.
+
+## Installation
+
+Add this marketplace to Claude Code:
+
+```bash
+/plugin marketplace add obra/superpowers-marketplace
+```
+
+## Available Plugins
+
+### Superpowers (Core)
+
+**Description:** Core skills library with TDD, debugging, collaboration patterns, and proven techniques
+
+**Categories:** Testing, Debugging, Collaboration, Meta
+
+**Install:**
+```bash
+/plugin install superpowers@superpowers-marketplace
+```
+
+**What you get:**
+- 20+ battle-tested skills
+- `/brainstorm`, `/write-plan`, `/execute-plan` commands
+- Skills-search tool for discovery
+- SessionStart context injection
+
+**Repository:** https://github.com/obra/superpowers
+
+---
+
+### Elements of Style
+
+**Description:** Writing guidance based on William Strunk Jr.'s The Elements of Style (1918)
+
+**Categories:** Writing, Documentation, Reference
+
+**Install:**
+```bash
+/plugin install elements-of-style@superpowers-marketplace
+```
+
+**What you get:**
+- `writing-clearly-and-concisely` skill
+- Complete 1918 reference text (~12k tokens)
+- All 18 rules for clear, concise writing
+- Grammar, punctuation, and composition guidance
+
+**Repository:** https://github.com/obra/the-elements-of-style
+
+---
+
+### Superpowers: Developing for Claude Code
+
+**Description:** Skills and resources for developing Claude Code plugins, skills, MCP servers, and extensions
+
+**Categories:** Development, Documentation, Claude Code, Plugin Development
+
+**Install:**
+```bash
+/plugin install superpowers-developing-for-claude-code@superpowers-marketplace
+```
+
+**What you get:**
+- `working-with-claude-code` skill with 42+ official documentation files
+- `developing-claude-code-plugins` skill for streamlined development workflows
+- Self-update mechanism for documentation
+- Complete reference for plugin development, skills, MCP servers, and extensions
+
+**Repository:** https://github.com/obra/superpowers-developing-for-claude-code
+
+---
+
+## Marketplace Structure
+
+```
+superpowers-marketplace/
+├── .claude-plugin/
+│   └── marketplace.json       # Plugin catalog
+└── README.md                  # This file
+```
+
+## Support
+
+- **Issues**: https://github.com/obra/superpowers-marketplace/issues
+- **Core Plugin**: https://github.com/obra/superpowers
+
+## License
+
+Marketplace metadata: MIT License
+
+Individual plugins: See respective plugin licenses