It’s not that it needs to be “woken up”. The ingress session needs to be valid. As far as I am aware there is no solution other than opening the Grafana panel at least once every time you browse to your home assistant dashboard. (see below)
There are other ways of including the graphs but these have issues too. e.g. using a generic camera, but it is low resolution and has a slow polling update.
EDIT: I just did a search and apparently you might be able to use the iframe method if you change some environment variables: Best way to get Grafana chart into Lovelace card - #69 by randytsuch