feat: enhance messaging system with user search and direct conversations

- Added user-to-user messaging via profile pages.
- Implemented user search functionality with instant result display in the messaging sidebar.
- Introduced support for temporary chat interfaces when messaging new users without prior conversations.
- Included "Message read status" updates with improved UX for message timestamps.

frontend/src/app/(dashboard)/user/[username]/page.tsx

@@ -1,12 +1,19 @@
 "use client";
 
-import { Calendar, Share2, User as UserIcon } from "lucide-react";
+import {
+	Calendar,
+	MessageCircle,
+	Share2,
+	User as UserIcon,
+} from "lucide-react";
+import Link from "next/link";
 import * as React from "react";
 import { toast } from "sonner";
 import { ContentList } from "@/components/content-list";
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
 import { Button } from "@/components/ui/button";
 import { Spinner } from "@/components/ui/spinner";
+import { useAuth } from "@/providers/auth-provider";
 import { ContentService } from "@/services/content.service";
 import { UserService } from "@/services/user.service";
 import type { User } from "@/types/user";
@@ -17,9 +24,12 @@ export default function PublicProfilePage({
 	params: Promise<{ username: string }>;
 }) {
 	const { username } = React.use(params);
+	const { user: currentUser, isAuthenticated } = useAuth();
 	const [user, setUser] = React.useState<User | null>(null);
 	const [loading, setLoading] = React.useState(true);
 
+	const isOwnProfile = currentUser?.username === username;
+
 	React.useEffect(() => {
 		UserService.getProfile(username)
 			.then(setUser)
@@ -93,7 +103,15 @@ export default function PublicProfilePage({
 								})}
 							</span>
 						</div>
-						<div className="flex justify-center md:justify-start pt-2">
+						<div className="flex flex-wrap justify-center md:justify-start gap-2 pt-2">
+							{!isOwnProfile && isAuthenticated && (
+								<Button size="sm" className="h-9 px-4" asChild>
+									<Link href={`/messages?user=${user.uuid}`}>
+										<MessageCircle className="h-4 w-4 mr-2" />
+										Message
+									</Link>
+								</Button>
+							)}
 							<Button
 								variant="outline"
 								size="sm"