* docs(alerting): improve `Intro > Alert rule evaluation` docs * Update Introduction to Grafana Alerting * Simplify `Intro > Alert rules` and related docs * minor copy change phrasing GMA and DS differences * fix vale error
* docs(alerting): Import to Grafana-managed rules * apply latest evaluation changes * Add additional conversion details to How it works section * fix ref link * fix Data source input name * more details about the `Target data source` input
