Add business dashboard dark mode from Super Admin theme setting.

Login and in-app surfaces follow tenant themeMode, matching customer dark tokens, with themed switches and tighter card/table chrome.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/business/src/components/ProductCard.module.css

@@ -7,6 +7,7 @@
   border: 1px solid var(--glass-border);
   border-radius: var(--radius);
   box-shadow: var(--glass-shadow);
+  overflow: hidden;
   transition: transform 0.2s, box-shadow 0.2s;
 }
 
@@ -34,16 +35,15 @@
   width: 100%;
   aspect-ratio: 1 / 1;
   overflow: hidden;
-  background: #ffffff;
+  background: var(--card-media-bg);
   border-bottom: 1px solid rgba(148, 163, 184, 0.12);
-  border-radius: calc(var(--radius) - 1px) calc(var(--radius) - 1px) 0 0;
 }
 
 .image {
   width: 100%;
   height: 100%;
-  object-fit: contain;
-  padding: 10px;
+  object-fit: cover;
+  display: block;
 }
 
 .imagePlaceholder {