feat: enhance job and user models with additional fields

- Added VideoID, UserID, and TimeLimit fields to the job model.
- Removed unused referral fields from the user model.
- Updated job creation and update logic to handle new fields.
- Refactored job service to work with updated job model.
- Replaced cache interface with Redis adapter in service layer.
- Introduced a Dead Letter Queue (DLQ) for failed jobs in Redis.
- Updated gRPC server to accommodate changes in job handling.
- Removed obsolete cache package and related files.

internal/middleware/authenticator.go

@@ -194,7 +194,7 @@ func (a *Authenticator) maybeCreateSubscriptionReminderPostAuth(ctx context.Cont
 
 	sentAt := now
 	notification := &model.Notification{
-		ID:          uuidString(),
+		ID:          uuid.New().String(),
 		UserID:      user.ID,
 		Type:        "billing.subscription_expiring",
 		Title:       "Plan expiring soon",
@@ -272,7 +272,3 @@ func mustMarshalAuthJSON(value any) string {
 	}
 	return string(encoded)
 }
-
-func uuidString() string {
-	return uuid.New().String()
-}