Add regional form evolution details

[jemarq04]

Change description

This PR adds evolution details regarding all regional forms (Alola, Galar, Hisui, and Paldea) including some related region-specific evolutions (e.g. Cyndaquil to Quilava at level 17 instead of 14, but only in Hisui).

This is related to issue #1396. In addition to new evolution details, region_id and base_form_id are renamed to be region and base_form to be consistent with other fields (similar to PR #1487). The base_form field was changed to a Pokemon model so that regional forms could be specified. These fields were also missing from tests, so they were added as well.

An unintended consequence of this is that the latest evolution detail will not necessarily reflect the current evolution (like the Cyndaquil example I gave previously). At some point I'd like to add something to make the current evolution method clearer (maybe even accessible by version group?) but while I tinker with that these additions should be added.

Contributor check list

• I have written a description of the contribution and explained its motivation.
• I have written tests for my code changes (if applicable).
• I have read and understood the AI Assisted Contribution guidelines.
• I will own this change in production, and I am prepared to fix any bugs caused by my code change.