Remove Firebase and Vercel deployment options

- Remove firebase package dependency
- Delete apphosting.yaml configuration file
- Update README.md to focus on AWS S3 deployment only
- Update CLAUDE.md documentation accordingly
- Clean up package-lock.json (removed 54 packages)

🤖 Generated with [Claude Code](https://claude.ai/code)

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

package.json

@@ -11,7 +11,7 @@
     "start": "next start",
     "lint": "next lint",
     "typecheck": "tsc --noEmit",
-    "deploy:s3": "npm run build && aws s3 sync out/ s3://$S3_BUCKET_NAME --delete",
+    "deploy:s3": "npm run build && dotenv -e .env.local -- aws s3 sync out/ s3://$S3_BUCKET_NAME --delete",
     "create-s3-bucket": "node scripts/create-s3-bucket.js",
     "prepare": "husky install"
   },
@@ -45,7 +45,6 @@
     "date-fns": "^3.6.0",
     "dotenv": "^16.5.0",
     "embla-carousel-react": "^8.6.0",
-    "firebase": "^11.9.1",
     "genkit": "^1.13.0",
     "lucide-react": "^0.475.0",
     "next": "15.3.3",
@@ -67,6 +66,7 @@
     "aws-cdk-lib": "^2.189.1",
     "constructs": "^10.4.2",
     "cross-env": "^7.0.3",
+    "dotenv-cli": "^8.0.0",
     "esbuild": "^0.25.5",
     "eslint": "^9.30.0",
     "eslint-config-next": "15.3.4",