Migrate Connect org logos to File type

Replace Organization.logoUrl and horizontalLogoUrl with nested File
objects whose downloadUrl points at /api/files/v1/public/{id}, matching
the Console migration.

Org logos are FileVisibilityPublic and served without HTTP auth, so
Connect File.downloadUrl is built eagerly in NewFile with no field-level
authorize. Logo loading moves to iam.OrganizationService.LogoFile and
HorizontalLogoFile; the old URL generators are removed.

Sync IAM Relay components and n8n organization operations. Add an e2e
test for Connect multipart logo upload and ExecuteConnectWithFile.

Signed-off-by: Ludovic Vielle <ludovic@probo.com>

pkg/server/api/connect/v1/gqlgen.yaml

@@ -38,6 +38,9 @@ models:
   CursorKey:
     model:
       - "go.probo.inc/probo/pkg/server/gqlutils/types/cursor.CursorKeyScalar"
+  BigInt:
+    model:
+      - "go.probo.inc/probo/pkg/server/gqlutils/types/bigint.BigIntScalar"
   EmailAddr:
     model:
       - "go.probo.inc/probo/pkg/server/gqlutils/types/mail.AddrScalar"