Remove unused weight-based method of scheduling

> [!NOTE]
> Migrated from [augurlabs/augur#3267](https://github.com/augurlabs/augur/issues/3267)
> Originally opened by `@MoralCode` on 2025-09-10

---

Per a recent meeting among several core augur maintainers, it sounds like there is a legacy method of scheduing tasks that involved calculating a weight and assigning it to each task.

It was mentioned by @IsaacMilarky that this is no longer used.

I think we should consider removing this old scheduling method (or at least commenting out the code and removing the DB columns.

This would mean removing all columns with names suffixed with `_weight` from the collection status table of the augur_operations database.