style: fix avatar image scaling in subscription section

Add CSS rules to ensure subscription avatars maintain proper aspect ratio and cover their container without distortion.

css/style.css

@@ -245,6 +245,12 @@ body {
     overflow: hidden;
 }
 
+.subscription-avatar img {
+    width: 100%;
+    height: 100%;
+    object-fit: cover;
+}
+
 .subscription-name {
     font-size: 14px;
     color: #ffffff;