Remove id autogeneration from db models

Remove automatic uuid v4 ID generation from the models and replace it
with `shared.NewId()`, which generates an Id depending on the config
setting

storage-new/models/MediaMetadata.go

@@ -12,7 +12,7 @@ import (
 // Instead, they are either stored on the remote server they originated from
 // or an s3 bucket if uploaded to Linstrom.
 type MediaMetadata struct {
-	ID        string    `gorm:"primarykey;default:gen_random_uuid()"` // The unique ID of this media file
+	ID        string    `gorm:"primarykey"` // The unique ID of this media file
 	CreatedAt time.Time // When this entry was created
 	UpdatedAt time.Time // When this entry was last updated
 	// When this entry was deleted (for soft deletions)