Read and change ClickHouse server settings on a Cloud service without SQL, using the Cloud API clickhouseSettings endpoints

Documented steps

1. Resolve organizationId and serviceId via GET /v1/organizations and GET /v1/organizations/{organizationId}/services if you do not already have them.
2. Discover what is settable: GET /v1/organizations/{organizationId}/services/{serviceId}/clickhouseSettings/schema returns a `settings` array of entries with name, type, description, enum (allowed values where applicable), warning, deprecationNotice, and example. Numeric bounds are not exposed as separate min/max fields.
3. List currently configured settings: GET /v1/organizations/{organizationId}/services/{serviceId}/clickhouseSettings returns {settings:[{name, value}]} and includes ONLY settings that have been explicitly set - platform defaults are omitted.
4. Read one setting with GET /v1/organizations/{organizationId}/services/{serviceId}/clickhouseSettings/{settingName}.
5. Update with PATCH /v1/organizations/{organizationId}/services/{serviceId}/clickhouseSettings. The required `settings` field is a JSON-ENCODED STRING of a name-to-value object, not a nested JSON object - the spec's own example is {"compatibility": "24.8"} passed as a string.
6. curl -u "$KEY_ID:$KEY_SECRET" -X PATCH https://api.clickhouse.cloud/v1/organizations/$ORG_ID/services/$SERVICE_ID/clickhouseSettings -H 'Content-Type: application/json' -d '{"settings": "{\"max_memory_usage\": \"10000000000\"}"}'
7. Inspect the response's `warnings` array ({name, message}) for disruptive-change alerts before treating the change as complete.
8. Revert a setting to the platform default with DELETE /v1/organizations/{organizationId}/services/{serviceId}/clickhouseSettings/{settingName}, e.g. .../clickhouseSettings/compatibility.
9. Verify by re-issuing the list GET and confirming the value appears (after PATCH) or is absent (after DELETE).
10. Docs: https://clickhouse.com/docs/cloud/manage/openapi and https://clickhouse.com/docs/cloud/manage/api/api-overview