feat: integrate TransactionHistory component into Dashboard and update styles for better UI consistency

src/pages/admin/AdminNewsletters.js

@@ -223,10 +223,13 @@ const AdminNewsletters = () => {
                 <Calendar className="h-5 w-5" />
                 {year}
               </h2>
-              <div className="grid gap-4">
+              <div className="grid gap-3">
                 {groupedNewsletters[year].map(newsletter => (
                   <Card key={newsletter.id} className="p-6">
-                    <div className="flex items-start justify-between">
+                    <div className="flex items-start justify-between ">
+                      <div className="bg-light-lavender p-3 mr-4 rounded-xl self-center">
+                        <FileText className="size-8 " />
+                      </div>
                       <div className="flex-1">
                         <h3 className="text-lg font-semibold text-[var(--purple-ink)] mb-2">
                           {newsletter.title}