more work on attachments

* fix frontend env usage

apps/server/src/core/attachment/dto/get-file.dto.ts

@@ -0,0 +1,7 @@
+import { IsNotEmpty, IsString } from 'class-validator';
+
+export class GetFileDto {
+  @IsString()
+  @IsNotEmpty()
+  attachmentId: string;
+}

apps/server/src/core/attachment/dto/upload-file.dto.ts

@@ -0,0 +1,20 @@
+import {
+  IsDefined,
+  IsNotEmpty,
+  IsOptional,
+  IsString,
+  IsUUID,
+} from 'class-validator';
+
+export class UploadFileDto {
+  @IsString()
+  @IsNotEmpty()
+  attachmentType: string;
+
+  @IsOptional()
+  @IsUUID()
+  pageId: string;
+
+  @IsDefined()
+  file: any;
+}