Update ci-book.yml

Author: arojascastro

.github/workflows/ci-book.yml

@@ -1 +1,27 @@
 # (paste the YAML above)
+name: ci-book
+
+on:
+  pull_request:
+  push:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements.txt
+
+      - name: Verify Jupyter Book builds (no deploy)
+        run: |
+          jupyter-book clean . --all
+          jupyter-book build . --all