CloudWatch targets missing metricQueryType/metricEditorMode silently show "No data" in UI

### What happened? When provisioning a CloudWatch dashboard via the API (e.g., using Terraform's `grafana_dashboard` resource), if the target JSON omits `metricQueryType` and `metricEditorMode` fields, the Grafana UI renders an empty "Choose" dropdown for "Metric editor mode" and **never fires any CloudWatch query**. Panels silently display "No data" with no error message. This is particularly confusing because: 1. The same queries work correctly when sent directly to `POST /api/ds/query` — the server-side query runner processes them fine. 2. No error appears in the panel, the browser console, or the network tab — the UI simply never initiates any requests. 3. There is no validation error when saving/importing the dashboard. ### What did you expect to happen? Either: - Default `metricQueryType` to `0` (Metric Search) and `metricEditorMode` to `0` (Builder) when these fields are absent, OR - Display a visible error or warning on the panel indicating the query configuration is incomplete. ### Did this work before? Haven't tested with prior versions of the plugin ### How do we reproduce it? 1. Create a CloudWatch data source in Grafana 10.4+ 2. Import a dashboard with a CloudWatch target that omits `metricQueryType` and `metricEditorMode`: ```json { "targets": [ { "refId": "A", "datasource": { "type": "cloudwatch", "uid": "cloudwatch" }, "namespace": "AWS/Lambda", "metricName": "Invocations", "dimensions": { "FunctionName": ["my-function"] }, "statistic": "Sum", "period": "60", "region": "us-west-2", "id": "", "expression": "", "matchExact": true } ] } ``` 3. Observe: panel shows "No data", metric editor shows empty "Choose" dropdown. 4. Add `"metricQueryType": 0, "metricEditorMode": 0` to the target — panel immediately works. ### Is the bug inside a dashboard panel? Unclear ### Environment (with versions)? - Grafana version: 10.4 (Amazon Managed Grafana) - Data source: CloudWatch - OS: N/A (…