[metrics][visualization] reporting metrics/visualization

per tc weekly on 2025 06 17

I raised two issues at the meeting:

1. the excel spreadsheet on sharepoint, for the metrics scraped from matomo, it would be good to have siteId and matomo base_url attribute populated. This way, service providers can quickly identify which metrics belong to which application fixed as of 20250723

2. (not sure if it is possible) to import metrics into, and visualize the said metrics, in grafana. (My monkey brain is telling me perhaps with a prometheus exporter, or just an aggregation script, which runs daily, and saves output as a text file).

2b. If the expected output can be documented, we can also imagine to be able to export metrics conforming to the metrics labels.