feat(admin): enhance editor UI (links, image captions) & fix categories

Added animated auto-opening link modal, custom image node with isolated caption deletion, fixed single-select category data binding, improved featured image layout, and updated README.

frontend/src/components/ArticleCard.tsx

@@ -3,6 +3,7 @@ import { Link } from 'react-router-dom'
 import { ArrowLeftIcon, ClockIcon } from 'lucide-react'
 import type { Article } from '../data/site'
 import { formatJalali } from '../utils/date'
+import { toPersianDigits } from '../utils/digits'
 
 export function ArticleCard({ article }: { article: Article }) {
   return (
@@ -37,7 +38,7 @@ export function ArticleCard({ article }: { article: Article }) {
             <span>{formatJalali(article.date)}</span>
             <span className="flex items-center gap-1.5">
               <ClockIcon className="h-3.5 w-3.5 text-copper/80" />
-              {article.read}
+              {toPersianDigits(article.read)}
             </span>
           </span>