grafana-step-create-annotation

This step adds an annotation to a Grafana dashboard using the Grafana Annotations API.

• If both dashboardId and panelId are omitted, the annotation will be global.
• If a dashboardId is provided, but a panelId is omitted, the annotations will be applied to all panels for the given dashboard.
• The start time defaults to the current time if not provided.
• The end time defaults to the start time if not provided.