Function POST

Returns Promise<
    | NextResponse<{ error: string }>
    | NextResponse<
        {
            success: boolean;
            message: string;
            data: {
                files: (
                    | {}
                    | {
                        id: string;
                        filename: string;
                        key: string;
                        mimetype: string;
                        size: number;
                        url: string;
                        postId: null;
                        employeeExpenseId: null;
                        employeeId: null;
                        companyId: null;
                        trainingId: null;
                        createdAt: Date;
                        updatedAt: Date;
                    }
                )[];
                uploadType: string;
                entityId: string;
            };
        },
    >,
>