fix(scim): create a real MySQL foreign key for scim_api_key

MySQL/InnoDB silently ignores inline column-level REFERENCES, so the original
migration created no foreign key at all on MySQL. Use a table-level FOREIGN KEY
clause and match organizations.uuid's VARCHAR(40) type exactly so the
constraint is actually created.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

migrations/mysql/2026-07-19-000000_add_scim_api_key/up.sql

@@ -1,8 +1,12 @@
+-- org_uuid is VARCHAR(40) to match organizations.uuid exactly; the FOREIGN KEY
+-- must be a table-level clause because MySQL silently ignores inline
+-- column-level REFERENCES.
 CREATE TABLE scim_api_key (
 	uuid            CHAR(36) NOT NULL PRIMARY KEY,
-	org_uuid        CHAR(36) NOT NULL UNIQUE REFERENCES organizations(uuid),
+	org_uuid        VARCHAR(40) NOT NULL UNIQUE,
 	key_hash        VARCHAR(255) NOT NULL,
 	enabled         BOOLEAN NOT NULL DEFAULT TRUE,
 	created_at      DATETIME NOT NULL,
-	revision_date   DATETIME NOT NULL
+	revision_date   DATETIME NOT NULL,
+	FOREIGN KEY(org_uuid) REFERENCES organizations(uuid)
 );