chore: remove unused system_fronters view

PluralKit.Core/Database/Views/views.sql

@@ -7,25 +7,6 @@ select systems.id     as system,
 from systems
     inner join lateral (select * from switches where switches.system = systems.id order by timestamp desc limit 1) as last_switch on true;
 
--- Returns one row for every current fronter in a system, w/ some member info
-create view system_fronters as
-select
-    systems.id            as system_id,
-    last_switch.id        as switch_id,
-    last_switch.timestamp as switch_timestamp,
-    members.id            as member_id,
-    members.hid           as member_hid,
-    members.name          as member_name
-from systems
-    -- TODO: is there a more efficient way of doing this search? might need to index on timestamp if we haven't in prod
-    inner join lateral (select * from switches where switches.system = systems.id order by timestamp desc limit 1) as last_switch on true
-
-    -- change to left join to handle memberless switches?
-    inner join switch_members on switch_members.switch = last_switch.system
-    inner join members on members.id = switch_members.member
--- return them in order of the switch itself
-order by switch_members.id;
-
 create view member_list as
 select members.*,
        -- Find last message ID