docs: add publishing guide with CI/CD setup

Author: r-el

PUBLISHING.md

@@ -0,0 +1,108 @@
+# Publishing Guide
+
+This guide explains how to publish new versions of JsonFileCRUD to npm.
+
+## Prerequisites
+
+1. **npm account**: Make sure you have an npm account and are logged in
+   ```bash
+   npm login
+   ```
+
+2. **npm token**: For GitHub Actions, add your npm token to repository secrets as `NPM_TOKEN`
+
+3. **Repository access**: Make sure you have push access to the GitHub repository
+
+## Publishing Process
+
+### Option 1: Manual Publishing (Recommended for first time)
+
+1. **Update version and changelog:**
+   ```bash
+   npm version patch    # for bug fixes
+   npm version minor    # for new features
+   npm version major    # for breaking changes
+   ```
+
+2. **Verify everything works:**
+   ```bash
+   npm test
+   npm run examples
+   ```
+
+3. **Check what will be published:**
+   ```bash
+   npm pack --dry-run
+   ```
+
+4. **Publish to npm:**
+   ```bash
+   npm publish
+   ```
+
+### Option 2: Automated Publishing via GitHub Releases
+
+1. **Create a new release on GitHub:**
+   - Go to the repository on GitHub
+   - Click "Releases" → "Create a new release"
+   - Tag version: `v1.0.0` (match package.json version)
+   - Release title: `Version 1.0.0`
+   - Description: Copy from CHANGELOG.md
+
+2. **GitHub Actions will automatically:**
+   - Run all tests
+   - Run examples
+   - Publish to npm (if tests pass)
+
+### Option 3: Using npm version command
+
+```bash
+# This will:
+# 1. Run tests
+# 2. Run examples  
+# 3. Update version in package.json
+# 4. Create git tag
+# 5. Push to GitHub
+npm version patch
+```
+
+Then create a GitHub release for the new tag to trigger npm publishing.
+
+## Version Guidelines
+
+- **Patch (1.0.X)**: Bug fixes, documentation updates
+- **Minor (1.X.0)**: New features, non-breaking changes
+- **Major (X.0.0)**: Breaking changes
+
+## Checklist Before Publishing
+
+- [ ] All tests pass (`npm test`)
+- [ ] Examples work (`npm run examples`)
+- [ ] CHANGELOG.md updated
+- [ ] README.md updated if needed
+- [ ] Version number updated in package.json
+- [ ] Git changes committed and pushed
+
+## Post-Publishing
+
+1. **Verify the package:**
+   ```bash
+   npm view json-file-crud
+   ```
+
+2. **Test installation:**
+   ```bash
+   mkdir test-install
+   cd test-install
+   npm init -y
+   npm install json-file-crud
+   ```
+
+3. **Update documentation** if needed
+
+## Troubleshooting
+
+- **403 Forbidden**: Make sure you're logged in and have permission to publish
+- **Version already exists**: Update the version number
+- **Tests fail**: Fix issues before publishing
+- **Missing files**: Check .npmignore and package.json files array