featmigrate from Angular to Astro static site

BREAKING CHANGE: Complete rewrite from Angular SPA to Astro

- Replace Angular 18 with Astro 5.16.7 + Tailwind CSS
- Convert all Angular components to Astro components
- Add content collections for blog with markdown support
- Setup S3 deployment with CloudFront invalidation
- Add RSS feed and sitemap generation
- Configure Prettier and Biome for code formatting
- Switch from npm to pnpm
- Remove Amplify backend (now fully static)
- Improve SEO and performance with static generation

.prettierrc.json

@@ -0,0 +1,19 @@
+{
+	"plugins": ["prettier-plugin-astro"],
+	"overrides": [
+		{
+			"files": "*.astro",
+			"options": {
+				"parser": "astro"
+			}
+		}
+	],
+	"semi": true,
+	"singleQuote": false,
+	"tabWidth": 2,
+	"useTabs": true,
+	"trailingComma": "es5",
+	"printWidth": 100,
+	"bracketSpacing": true,
+	"arrowParens": "always"
+}