feat: add official EmDash marketing template

- Marketing landing page with hero, features, testimonials, FAQ, pricing
- EmDash CMS with pages collection and marketing blocks
- Full seed data with all content sections
- Dockerfile with entrypoint for database persistence
- Responsive design with CSS variables

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "extends": "astro/tsconfigs/strict",
+  "compilerOptions": {
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["src/*"]
+    }
+  }
+}