fix(infra): add required id field to n8n credential import

n8n import:credentials requires an id field — SQLITE_CONSTRAINT
NOT NULL on credentials_entity.id.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ImTotem

infra/scripts/init_n8n.sh

@@ -64,6 +64,7 @@ setup_credential() {
 import json, sys
 sa = json.load(open('$GOOGLE_SERVICE_ACCOUNT_FILE'))
 cred = [{
+    'id': '1',
     'name': 'Google Sheets SA',
     'type': 'googleApi',
     'data': {