[feature] persist worker queues to db (#3042)

* persist queued worker tasks to database on shutdown, fill worker queues from database on startup

* ensure the tasks are sorted by creation time before pushing them

* add migration to insert WorkerTask{} into database, add test for worker task persistence

* add test for recovering worker queues from database

* quick tweak

* whoops we ended up with double cleaner job scheduling

* insert each task separately, because bun is throwing some reflection error??

* add specific checking of cancelled worker contexts

* add http request signing to deliveries recovered from database

* add test for outgoing public key ID being correctly set on delivery

* replace select with Queue.PopCtx()

* get rid of loop now we don't use it

* remove field now we don't use it

* ensure that signing func is set

* header values weren't being copied over 🤦

* use ptr for httpclient.Request in delivery

* move worker queue filling to later in server init process

* fix rebase issues

* make logging less shouty

* use slices.Delete() instead of copying / reslicing

* have database return tasks in ascending order instead of sorting them

* add a 1 minute timeout to persisting worker queues

internal/gtsmodel/workertask.go

@@ -34,8 +34,8 @@ const (
 // queued tasks from being lost. It is simply a
 // means to store a blob of serialized task data.
 type WorkerTask struct {
-	ID         uint      `bun:""`
-	WorkerType uint8     `bun:""`
-	TaskData   []byte    `bun:""`
-	CreatedAt  time.Time `bun:""`
+	ID         uint       `bun:",pk,autoincrement"`
+	WorkerType WorkerType `bun:",notnull"`
+	TaskData   []byte     `bun:",nullzero,notnull"`
+	CreatedAt  time.Time  `bun:"type:timestamptz,nullzero,notnull,default:current_timestamp"`
 }