[client] Add "value" attribute to candidates of "minimum severity"

Because labels may be changed later.
[TriggersView] Migrate to server side filter
[TriggersView] Remove needless code
[OverviewTriggers] Migrate to server side filter
[OverviewTriggers] Remove needless code
[OverviewTriggers] Break long lines
[OverviewItems] Migrate to server side filter
[OverviewItems] Remove needless code
[OverviewItems] Break a long line
[LatestView] Migrate to server side filter except "Application"
[LatestView] Remove needless code