refactor: remove departmentId from Class entity

apps/server/src/classes/dto/class.dto.ts

@@ -9,8 +9,6 @@ export class CreateClassDto {
   @IsString() @IsNotEmpty()
   code: string;
 
-  @IsOptional() @IsInt()
-  departmentId?: number;
 
   @IsEnum(ClassType) @IsString() @IsNotEmpty()
   classType: string;
@@ -58,8 +56,6 @@ export class UpdateClassDto {
   @IsOptional() @IsString()
   code?: string;
 
-  @IsOptional() @IsInt()
-  departmentId?: number;
 
   @IsEnum(ClassType) @IsOptional() @IsString()
   classType?: string;
@@ -90,10 +86,6 @@ export class UpdateClassDto {
 }
 
 export class QueryClassDto {
-  @IsOptional()
-  @Type(() => Number)
-  @IsInt()
-  departmentId?: number;
 
   @IsOptional() @IsString()
   status?: string;