fix(imgproxy): fallback to smart gravity (sm) instead of face detection (fv)

- 'fv' requires ML modules not present in standard imgproxy image
- 'sm' is robust and supported everywhere
- Fixes broken images on staging using Next.js Image loader

lib/imgproxy-loader.ts

@@ -28,6 +28,6 @@ export default function imgproxyLoader({
   return getImgproxyUrl(src, {
     width,
     resizing_type: 'fit',
-    gravity: 'fv', // Use face-aware focusing (face detection)
+    gravity: 'sm', // Use smart gravity (content-aware) instead of face detection (requires ML)
   });
 }

lib/imgproxy.ts

@@ -60,5 +60,5 @@ export function getImgproxyUrl(src: string, options: ImgproxyOptions = {}): stri
   // Format: <base_url>/unsafe/<options>/plain/<source_url>[@<extension>]
   const suffix = extension ? `@${extension}` : '';
 
-  return `${baseUrl}/unsafe/${processingOptions}/plain/${absoluteSrc}${suffix}`;
+  return `${baseUrl}/unsafe/${processingOptions}/plain/${encodeURIComponent(absoluteSrc)}${suffix}`;
 }