8fd1d83b1b
## Why
The grafana-operator estate has no dashboard for Redis/Valkey; redis_exporter instances are being added in a parallel PR and need visibility.
## Changes
- Adds `apps/base/grafana/dashboards/redis.yaml`, a GrafanaDashboard CR embedding grafana.com dashboard 763 ("Redis Dashboard for Prometheus Redis Exporter 1.x") as gzipJson like the sibling dashboards, with namespace/instance template variables over `redis_up` for multi-instance use and all datasource refs pinned to the VictoriaMetrics datasource uid (`det2y55dac4jkc`), registered in the grafana kustomization
Reviewed-on: #396
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>