FEAT: Ability to set sub labels for specific events (#2949)

* Add sub label to model and set / delete funs

* Add migrations for sub label

* Tweaks to API and model

* Show sublabel if available

* Cleanups

* Update docs

* Show person in UI title

* Fix typo and don't fail on no json

* Transfer sub labels for in progress events

* Remove sublabel reset

* Remove person only check

* Make default null

* Update docs and formatting

* Make default null

* Make nullable in migration

* Undo null

* Update model to accept null

* Update migration to accept null

* Don't set to default values

* Remove redundant defaults and update http logic

* Only need a single route

* Enforce 20 character limit in http

* Update docs to mention 20 character limit

* Cleanup

* Separate insert and update to make sure updated values are retained when event ends

* Use insert instead of replace

* Remove redundant if and have should_update_db include clip or snapshot requirement.

web/src/routes/Events.jsx

@@ -315,7 +315,7 @@ export default function Events({ path, ...props }) {
                     <div className="m-2 flex grow">
                       <div className="flex flex-col grow">
                         <div className="capitalize text-lg font-bold">
-                          {event.label} ({(event.top_score * 100).toFixed(0)}%)
+                          {event.sub_label ? `${event.label}: ${event.sub_label}` : event.label} ({(event.top_score * 100).toFixed(0)}%)
                         </div>
                         <div className="text-sm">
                           {new Date(event.start_time * 1000).toLocaleDateString()}{' '}