Update alert rule UI to use health risks

[Velcrow81]

Hide manual input to Health Risk number and instead set this value by selection a health risk from a drop down.

If we get an existing alert rule, this selection should be reflected in list

Default the alert rule name to the health risk name

Change UI for timefram to whole days (but convert to hours for backend)

Change UI for distance in whole kilometers (but convert to meters for backend)

UX should be updated to reflect this. Other than that, it should mostly be front end