Fix: Optimized the table of contents style and homepage card layout #3221 (#9993)

### What problem does this PR solve?

Fix: Optimized the table of contents style and homepage card layout
#3221

- Added background color, text color, and shadow styles to the Markdown
table of contents
- Optimized the date display style in the HomeCard component to prevent
overflow
- Standardized the translation of "dataset" to "knowledge base" to
improve terminology consistency

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

web/src/components/home-card.tsx

@@ -44,7 +44,7 @@ export function HomeCard({ data, onClick, moreDropdown, sharedBadge }: IProps) {
               {data.description}
             </div>
             <div className="flex justify-between items-center">
-              <p className="text-sm opacity-80">
+              <p className="text-sm opacity-80 whitespace-nowrap">
                 {formatDate(data.update_time)}
               </p>
               {sharedBadge}