Alerting: Allow disabling recording rules write for a data source in the UI (#106664)

Adds a new "Allow as recording rules target" toggle to Prometheus datasource configuration that controls whether the datasource can be selected as a target for writing recording rules.
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Co-authored-by: ismail simsek <ismailsimsek09@gmail.com>
Co-authored-by: Konrad Lalik <konradlalik@gmail.com>

packages/grafana-runtime/src/config.ts

@@ -193,6 +193,7 @@ export class GrafanaBootConfig implements GrafanaConfig {
     connMaxLifetime: 14400,
   };
   defaultDatasourceManageAlertsUiToggle = true;
+  defaultAllowRecordingRulesTargetAlertsUiToggle = true;
 
   tokenExpirationDayLimit: undefined;
   enableFrontendSandboxForPlugins: string[] = [];