ui/admin: add message logs notification count line graph

[Forfold]

Part of #2460, related to #2600

• Updated the top controls to better fit the graph
• Uses the first and last dates of the currently fetched message logs for the initial graph display
• Prioritizes using the start/end times for the graph display, if set in the filter controls up top
• Shows line graph of counts by day on the route for message logs
• The graph can be hidden under an accordion
• The page title reads "Message Logs" instead of "message-logs"
• Notifications that get bundled are omitted from showing (as nothing is actually sent to the user for these log entries)
• Can change the interval of the graph to go by daily, hourly, or by the minute. Default: daily

[tony-tvu]

lgtm

[mastercactapus]

Jumping on a different issue, but possible TODO: fill in the gaps with zeros. The backend returns sparse data, so the graph only displays counts >0. We could fix this in either place, but it's probably the cleanest/easiest in Go from the service side.

[m17ch]

LGTM 👍