fix: replace punycode with native http/https modules

.github/workflows/node.yml

@@ -0,0 +1,25 @@
+name: Node.js CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [16.x, 18.x, 20.x]
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v3
+      with:
+        node-version: ${{ matrix.node-version }}
+        cache: 'npm'
+    - run: npm install
+    - run: npm test

CLAUDE.md

@@ -0,0 +1,27 @@
+# html2thermal Project Guidelines
+
+## Commands
+- Run all tests: `npm test`
+- Run specific test: `npx mocha -g "test pattern"`
+
+## Code Style
+- **Modules**: CommonJS (`require`/`module.exports`)
+- **Variables**: Prefer `const`, use `let` when needed
+- **Functions**: Use arrow functions for simple cases
+- **Naming**: camelCase for variables/functions/files
+- **Indentation**: 2 spaces
+- **Strings**: Single quotes
+- **File Organization**:
+  - Tag handlers in `src/convert/[tagName]TagHandler.js`
+  - Utility functions in `src/utils/`
+
+## Patterns
+- Functional approach with minimal state
+- Handler pattern for different HTML tags
+- Central processing in `src/convert/index.js`
+- Return `null` for special conditions instead of throwing errors
+- Tests use Mocha with describe/it blocks and assert.deepStrictEqual
+
+## Dependencies
+- Core: cheerio, sanitize-html, jimp, lodash, node-thermal-printer
+- Test: mocha, probe-image-size