feat: implement messaging functionality with real-time updates

- Introduced a messaging module on the backend using NestJS, including repository, service, controller, DTOs, and WebSocket Gateway.
- Developed a frontend messaging page with conversation management, real-time message handling, and chat UI.
- Implemented `MessageService` for API integrations and `SocketProvider` for real-time WebSocket updates.
- Enhanced database schema to support conversations, participants, and messages with Drizzle ORM.

backend/src/realtime/events.gateway.ts

@@ -0,0 +1,82 @@
+import { Logger } from "@nestjs/common";
+import { ConfigService } from "@nestjs/config";
+import {
+	OnGatewayConnection,
+	OnGatewayDisconnect,
+	OnGatewayInit,
+	WebSocketGateway,
+	WebSocketServer,
+} from "@nestjs/websockets";
+import { getIronSession } from "iron-session";
+import { Server, Socket } from "socket.io";
+import { getSessionOptions, SessionData } from "../auth/session.config";
+import { JwtService } from "../crypto/services/jwt.service";
+
+@WebSocketGateway({
+	cors: {
+		origin: "*",
+		credentials: true,
+	},
+})
+export class EventsGateway
+	implements OnGatewayInit, OnGatewayConnection, OnGatewayDisconnect
+{
+	@WebSocketServer()
+	server!: Server;
+
+	private readonly logger = new Logger(EventsGateway.name);
+
+	constructor(
+		private readonly jwtService: JwtService,
+		private readonly configService: ConfigService,
+	) {}
+
+	afterInit(_server: Server) {
+		this.logger.log("WebSocket Gateway initialized");
+	}
+
+	async handleConnection(client: Socket) {
+		try {
+			// Simuler un objet Request/Response pour iron-session
+			const req: any = {
+				headers: client.handshake.headers,
+			};
+			const res: any = {
+				setHeader: () => {},
+				getHeader: () => {},
+			};
+
+			const session = await getIronSession<SessionData>(
+				req,
+				res,
+				getSessionOptions(this.configService.get("SESSION_PASSWORD") as string),
+			);
+
+			if (!session.accessToken) {
+				this.logger.warn(`Client ${client.id} unauthorized connection`);
+				client.disconnect();
+				return;
+			}
+
+			const payload = await this.jwtService.verifyJwt(session.accessToken);
+			client.data.user = payload;
+			
+			// Rejoindre une room personnelle pour les notifications
+			client.join(`user:${payload.sub}`);
+
+			this.logger.log(`Client connected: ${client.id} (User: ${payload.sub})`);
+		} catch (error) {
+			this.logger.error(`Connection error for client ${client.id}: ${error}`);
+			client.disconnect();
+		}
+	}
+
+	handleDisconnect(client: Socket) {
+		this.logger.log(`Client disconnected: ${client.id}`);
+	}
+
+	// Méthode utilitaire pour envoyer des messages à un utilisateur spécifique
+	sendToUser(userId: string, event: string, data: any) {
+		this.server.to(`user:${userId}`).emit(event, data);
+	}
+}