feat: schema-builder and resolver-builder can handle relations (#2398)

* feat: wip add relation

* feat: add relation for custom and standards objects

* fix: use enum instead of magic string

* fix: remove dead code & fix tests

* fix: typo

* fix: BooleanFilter is missing

* fix: Malformed result error

server/src/metadata/relation-metadata/dtos/create-relation.input.ts

@@ -9,16 +9,16 @@ import {
   IsUUID,
 } from 'class-validator';
 
-import { RelationType } from 'src/metadata/relation-metadata/relation-metadata.entity';
+import { RelationMetadataType } from 'src/metadata/relation-metadata/relation-metadata.entity';
 import { BeforeCreateOneRelation } from 'src/metadata/relation-metadata/hooks/before-create-one-relation.hook';
 
 @InputType()
 @BeforeCreateOne(BeforeCreateOneRelation)
 export class CreateRelationInput {
-  @IsEnum(RelationType)
+  @IsEnum(RelationMetadataType)
   @IsNotEmpty()
   @Field()
-  relationType: RelationType;
+  relationType: RelationMetadataType;
 
   @IsUUID()
   @IsNotEmpty()