⌚ Add CI for building book PDF

.github/workflows/build-pdf.yml

@@ -0,0 +1,49 @@
+name: Compile LaTeX and Publish PDF
+
+on:
+  push:
+    branches:
+      - main
+      - '*'
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+jobs:
+  build-and-release:
+    runs-on: ubuntu-latest
+
+    steps:
+      # 1. Checkout repository code
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      # 2. Compile LaTeX book to PDF
+      - name: Compile LaTeX
+        uses: xu-cheng/latex-action@v3
+        with:
+          root_file: book.tex
+
+      # 3. Save PDF as an Actions artifact (for downloading from the workflow run tab)
+      - name: Upload Artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: compiled-book
+          path: book.pdf
+
+      # 4. Create or update the 'latest' GitHub Release
+      - name: Publish to GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: latest
+          name: "Latest Book Build"
+          body: "Automated build compiled from the latest push to `main`."
+          draft: false
+          prerelease: false
+          files: book.pdf
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}