Let hero stats cards auto-expand to fit long values.

Replace fixed mobile widths and equal grid columns with content-sized cards so figures like GHS balances and storage sizes are never clipped.

resources/css/app.css

@@ -101,7 +101,10 @@ html.qr-mobile-page body {
 }
 
 .mobile-stats-card {
-    width: calc(66.666667% - 0.5rem);
+    width: max-content;
+    min-width: 9rem;
+    max-width: none;
+    box-sizing: border-box;
 }
 
 @layer components {
@@ -334,7 +337,10 @@ html.qr-mobile-page body {
 
 @media (min-width: 640px) {
     .mobile-stats-card {
-        width: auto;
+        width: max-content;
+        min-width: 9rem;
+        max-width: none;
+        flex: 1 1 auto;
     }
 }