Connect - Relation on FE Importer (#13213)

Done : 
- Relation connect on FE Importer
- Remove templating on SpreadsheetMatchedColumn type
- Remove useless files on import
- Remove AvailableFieldsForImport type + Update SpreadsheetImportField
type and SpreadsheetImportFieldOption


To test : 
- Try import opportunities on Apple wk 
[using this
file](https://github.com/user-attachments/files/21233720/Test.import.-.opportunities-sample.csv)


closes : https://github.com/twentyhq/core-team-issues/issues/1090

packages/twenty-server/src/engine/metadata-modules/field-metadata/composite-types/full-name.composite-type.ts

@@ -10,14 +10,14 @@ export const fullNameCompositeType: CompositeType = {
       type: FieldMetadataType.TEXT,
       hidden: false,
       isRequired: false,
-      isIncludedInUniqueConstraint: true,
+      isIncludedInUniqueConstraint: false,
     },
     {
       name: 'lastName',
       type: FieldMetadataType.TEXT,
       hidden: false,
       isRequired: false,
-      isIncludedInUniqueConstraint: true,
+      isIncludedInUniqueConstraint: false,
     },
   ],
 };