feat: created DTO for category, director and movie

backend/src/dto/categoryDto.ts

+import { IMovieDto } from "./movieDto";
+
+export interface ICategoryDto {
+  id: string;
+  name: string;
+  movies: IMovieDto[];
+}

backend/src/dto/directorDto.ts

+import { IMovieDto } from "./movieDto";
+
+export interface IDirectorDto {
+  id: string;
+  name: string;
+  surname: string;
+  birthDate: Date;
+  movies: IMovieDto[];
+}

backend/src/dto/movieDto.ts

+import { ICategoryDto } from "./categoryDto";
+import { IDirectorDto } from "./directorDto";
+
+export interface IMovieDto {
+  id: string;
+  name: string;
+  originalName: string;
+  intro: string;
+  picture?: string;
+  publishedAt: Date;
+  runTimeMinutes: number;
+  director: IDirectorDto;
+  categories: ICategoryDto[];
+}