Estimate costs for baseline architecture for titiler-pgstac and titiler-xarray

We want to compare the costs of managing a COG archive vs a Zarr archive to balance any performance tradeoffs there may be in tiling. This will ideally use the same dataset as https://github.com/developmentseed/tile-benchmarking/issues/5

This cost estimate should include for titiler-pgstac:
- Generating + maintaining COGs
- Generating + maintaining STAC
- Storing COGs + STAC
- Cost for tiler lambda (requests)

This cost estimate should include for titiler-xarray:
- Generating + maintaining kerchunk reference
- Cost for tiler lambda (requests)
- ? Should we still assume the cost of running a pgSTAC instance? Probably yes, but the number of items would presumably be ~0 since zarrs are often being cataloged at the collection level

All estimates should be done in code so we can modify parameters for future datasets or architecture configurations