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/graphql/file.graphql

@@ -0,0 +1,12 @@
+# Connect File is PUBLIC-ONLY: downloadUrl points at /api/files/v1/public/{id}
+# and carries no authorization. Do not expose a private file through this type
+# without adding a forceResolver + auth on downloadUrl.
+type File {
+    id: ID!
+    mimeType: String!
+    fileName: String!
+    size: BigInt!
+    downloadUrl: String!
+    createdAt: Datetime!
+    updatedAt: Datetime!
+}