feat: add comments functionality and integrate Socket.io for real-time updates

- Implemented a full comments module in the backend with repository, service, controller, and DTOs using NestJS.
- Added frontend support for comments with a `CommentSection` component and integration into content pages.
- Introduced `SocketProvider` on the frontend and integrated Socket.io for real-time communication.
- Updated dependencies and configurations for Socket.io and WebSockets support.

backend/src/comments/dto/create-comment.dto.ts

@@ -0,0 +1,8 @@
+import { IsNotEmpty, IsString, MaxLength } from "class-validator";
+
+export class CreateCommentDto {
+	@IsString()
+	@IsNotEmpty()
+	@MaxLength(1000)
+	text!: string;
+}