feat: initial project setup

.github/workflows/ci.yml

@@ -0,0 +1,57 @@
+name: CI - Build Check
+
+on:
+  pull_request:
+    branches: [main]
+    types: [opened, synchronize, reopened]
+
+permissions:
+  contents: read
+  pull-requests: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    name: Build & Validate
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Type check
+        run: npm run astro check
+
+      - name: Build site
+        run: npm run build
+
+      - name: Comment PR on success
+        uses: actions/github-script@v7
+        if: success()
+        with:
+          script: |
+            github.rest.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: '✅ Build exitoso. El sitio compila correctamente. Listo para revisión.'
+            })
+
+      - name: Comment PR on failure
+        uses: actions/github-script@v7
+        if: failure()
+        with:
+          script: |
+            github.rest.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: '❌ Build fallido. Revisar los errores antes de mergear.'
+            })