Installs yesoreyeram-infinity-datasource on the Grafana pod so it can call
Actual's own ActualQL run-query endpoint directly (group-by/sum over any
field), instead of being limited to the fixed counters
actual-budget-exporter publishes. The datasource connection itself (URL +
x-api-key) is added by hand in the Grafana UI, not provisioned here — keeps
the API key out of git without needing a dedicated K8s Secret for it.