Add developer documentation for create-atxp package

- Create comprehensive README.md for developers working on create-atxp
- Document wrapper architecture and data flow
- Add detailed testing instructions with examples
- Include troubleshooting guide for common issues
- Document version management and publishing workflow
- Add testing checklist for releases
- Explain npm create syntax and how wrapper transforms calls

This helps developers understand and maintain the create-atxp wrapper.

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

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

Author: robdimarco-atxp

packages/create-atxp/README.md

@@ -0,0 +1,163 @@
+# create-atxp
+
+Developer documentation for the `create-atxp` wrapper package.
+
+## Overview
+
+The `create-atxp` package is a thin wrapper that enables the `npm create atxp` syntax by proxying calls to the main `atxp` package. This follows the convention used by other CLI tools like `create-react-app`, `create-next-app`, etc.
+
+## Architecture
+
+```
+npm create atxp my-app --framework express
+        ↓
+create-atxp/index.js
+        ↓  
+npx atxp create my-app --framework express
+        ↓
+packages/atxp/src/index.ts
+```
+
+### How it works:
+1. User runs `npm create atxp <args>`
+2. npm automatically runs `npx create-atxp <args>`
+3. `create-atxp/index.js` transforms this into `npx atxp create <args>`
+4. The main `atxp` package handles the actual project creation
+
+## Development
+
+### Prerequisites
+- Node.js 18+
+- The main `atxp` package built and available
+
+### Setup
+```bash
+cd packages/create-atxp
+npm install
+```
+
+### Testing the Wrapper
+
+#### Test Basic Functionality
+```bash
+# From packages/create-atxp directory
+node index.js test-app
+
+# Should be equivalent to:
+# npx atxp create test-app
+```
+
+#### Test with Flags
+```bash
+# Test framework flag
+node index.js test-app --framework express
+
+# Test git flags  
+node index.js test-app --no-git
+node index.js test-app --git
+
+# Test help
+node index.js --help
+```
+
+#### Test npm create Syntax
+```bash
+# From repo root, test the actual npm create flow
+npm create atxp test-app
+npm create atxp test-app --framework express --no-git
+```
+
+### Debugging
+
+#### Enable Verbose Output
+```bash
+# See exactly what command is being executed
+node index.js test-app --verbose
+```
+
+#### Check Dependencies
+```bash
+# Verify atxp package is available
+npx atxp --help
+
+# Check if create-atxp can find atxp
+npm ls atxp
+```
+
+### Common Issues
+
+#### "Command not found" errors
+- Ensure `atxp` package is built: `cd ../atxp && npm run build`
+- Check that `atxp` is in dependencies: check `package.json`
+
+#### Arguments not passing through
+- Verify `process.argv.slice(2)` is correctly capturing all arguments
+- Test with `console.log(atxpArgs)` in `index.js`
+
+#### Version mismatches
+- Both packages should have the same version number
+- Check `atxp` dependency version in `package.json`
+
+## Version Management
+
+The `create-atxp` package version should always match the main `atxp` package:
+
+```bash
+# Check current versions
+cd packages/atxp && npm version
+cd ../create-atxp && npm version
+
+# Update versions (should be done together)
+npm version patch  # in both packages
+```
+
+## Testing Checklist
+
+Before releasing, verify:
+
+- [ ] `node index.js test-app` creates project successfully
+- [ ] `node index.js test-app --framework express` works  
+- [ ] `node index.js test-app --no-git` skips git initialization
+- [ ] `node index.js test-app --git` forces git initialization
+- [ ] `node index.js --help` shows help information
+- [ ] `npm create atxp test-app` works from repo root
+- [ ] All arguments pass through correctly
+- [ ] Error messages are clear and helpful
+- [ ] Package.json versions match between both packages
+
+## File Structure
+
+```
+packages/create-atxp/
+├── README.md           # This developer documentation
+├── package.json        # Package configuration and dependencies
+├── index.js           # Main wrapper script
+└── eslint.config.js   # ESLint configuration
+```
+
+## Dependencies
+
+- **`atxp`**: The main CLI package (exact version match)
+- **`eslint`**, **`globals`**: Development dependencies for linting
+
+## Publishing
+
+This package is published to npm as `create-atxp` and should be published alongside the main `atxp` package with matching versions.
+
+```bash
+# Build and test first
+npm run build
+npm test
+
+# Publish (from packages/create-atxp)
+npm publish
+```
+
+## Contributing
+
+When modifying the wrapper:
+1. Test locally with `node index.js`
+2. Test with `npm create atxp` syntax  
+3. Verify all flags and arguments pass through
+4. Update tests if needed
+5. Ensure version stays in sync with main package