feat: enhance SSR routing and development experience

- Updated the SSR routing to conditionally load development and production handlers based on the NODE_ENV variable.
- Introduced a new dev.ts file to handle requests in development mode, including asset proxying and HTML response generation.
- Removed the not-found.tsx file and streamlined the photoId route logic for better maintainability.
- Added support for Open Graph and Twitter meta tags in the production handler for improved SEO.
- Updated README with new S3 endpoint configuration.

Signed-off-by: Innei <tukon479@gmail.com>

README.md

@@ -174,7 +174,8 @@ Create `builder.config.json` file for advanced configuration:
     "bucket": "my-photos",
     "region": "us-east-1",
     "prefix": "photos/",
-    "customDomain": "https://cdn.example.com"
+    "customDomain": "https://cdn.example.com",
+    "endpoint": "https://s3.amazonaws.com"
   },
   "options": {
     "defaultConcurrency": 8,