Files v2 - Add new FILES field type (#17236)

In this PR : 
- New field type FieldMetadataType.FILES added (as jsonb in DB)
- Backend: GraphQL types, validation, REST API schema, data processor
handling
- Frontend: field configuration in settings
- Feature flag IS_FILES_FIELD_ENABLED to gate the feature
- Integration tests for create/filter validation
- Dev seed: Feature flag enabled + FILES field on survey result object


To do in next PRs : 
- Backend : 
-- new workspaceFile controller (for download) & new workspaceFile
upload resolver (for upload)
-- pre-hook/post-hook to ensure fileId existence + listener to ensure
cleaning
- Frontend : FILES field display/edit in table view, record, ...

packages/twenty-front/src/generated/graphql.ts

@@ -1421,6 +1421,7 @@ export enum FeatureFlagKey {
   IS_COMMAND_MENU_ITEM_ENABLED = 'IS_COMMAND_MENU_ITEM_ENABLED',
   IS_DASHBOARD_V2_ENABLED = 'IS_DASHBOARD_V2_ENABLED',
   IS_EMAILING_DOMAIN_ENABLED = 'IS_EMAILING_DOMAIN_ENABLED',
+  IS_FILES_FIELD_ENABLED = 'IS_FILES_FIELD_ENABLED',
   IS_IF_ELSE_ENABLED = 'IS_IF_ELSE_ENABLED',
   IS_JSON_FILTER_ENABLED = 'IS_JSON_FILTER_ENABLED',
   IS_PAGE_LAYOUT_ENABLED = 'IS_PAGE_LAYOUT_ENABLED',
@@ -1500,6 +1501,7 @@ export enum FieldMetadataType {
   DATE = 'DATE',
   DATE_TIME = 'DATE_TIME',
   EMAILS = 'EMAILS',
+  FILES = 'FILES',
   FULL_NAME = 'FULL_NAME',
   LINKS = 'LINKS',
   MORPH_RELATION = 'MORPH_RELATION',