chore: switch engraft to @smartcompanion/engraft npm package

Replaces the pip-installed engraft (Python) with the published npm
package, removing the Python toolchain from CI. Renames the
examples/ directory to customization/ to better reflect its purpose.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: stefanhuber

.github/workflows/release.yml

@@ -33,11 +33,7 @@ jobs:
         with:
           node-version: 22
           cache: npm
-      - uses: actions/setup-python@v5
-        with:
-          python-version: '3.12'
       - run: npm ci
-      - run: pip install engraft
 
       # Build default "animals" variant
       - run: npm run build
@@ -47,7 +43,7 @@ jobs:
       - run: mv www animals
 
       # Build "leon" variant via engraft
-      - run: engraft apply --template engraft.template.yml --values examples/leon/engraft.variables.yml
+      - run: npx engraft apply --template engraft.template.yml --values customization/leon/engraft.variables.yml
       - run: npm run build
       - run: |
           sed -i 's|"/build/|"build/|g' www/index.html

README.md

@@ -48,7 +48,13 @@ npm run test:dev   # Continuous test watching
 
 ## Customization
 
-Customization is handled via [engraft](https://github.com/smartcompanion-app/engraft) using the `engraft.template.yml` file. All configurable variables are listed below:
+Customization is handled via [engraft](https://github.com/smartcompanion-app/engraft), which is included as the `@smartcompanion/engraft` devDependency. After `npm install`, apply a values file with:
+
+```bash
+npx engraft apply --template engraft.template.yml --values customization/leon/engraft.variables.yml
+```
+
+A ready-to-use example lives in [`customization/leon/`](customization/leon/) — copy that directory to start your own variant. All configurable variables defined in `engraft.template.yml` are listed below:
 
 | Variable | Description | Default |
 |---|---|---|