implement units of measure for distances in attributes

## Type of Issue

Select the type of issue:
- [ ] Bug report (to report a bug)
- [x] Feature request (to request an additional feature)
- [ ] Tracker (I am just using this as a tracker)
- [ ] Refactor request
- [ ] Documentation Ask

## Description

can just do in the most brutal way for rn, see here:
https://github.com/fairinternal/minecraft/blob/master/base_agent/memory_values.py#L39
and put here:
https://github.com/fairinternal/minecraft/blob/master/base_agent/dialogue_objects/attribute_helper.py#L102