Better comparison of retrievability scores across different subnets

[pyropy]

We initially created a retrievability score (RSR) focused on measuring Filecoin storage provider performance. As our analysis expanded to include additional networks like Arweave and Walrus, we found that this original scoring system doesn't effectively measure "performance" across all networks due to their different underlying designs.

We need to develop new measurements and refine our existing metrics to create a more standardised retrievability scoring system that works across all networks, allowing for fair "apples-to-apples" comparisons.