Add tests with validator set changes at forks

[leolara]

This branch introduces a new testing framework for fork transitions that focuses on scenarios where validators change state during the fork transition. The main goals are:

1. Template Test Infrastructure: Introduces a new template-based testing system
   (template_test.py) that allows for automated generation of tests across all fork
   transitions, making it easier to ensure consistent testing coverage. It also can be useful when many slightly different tests should be implemented.
2. Validator State Change Coverage: Specifically tests edge cases where validators
   exit, activate, or have their balances modified during the fork transition,
   ensuring the fork logic correctly handles these concurrent state changes.

The template test infrastructure is less than 180 lines of code, and 1300+ lines of code are unit tests for this infrastructure.

[leolara]

@potuz is this what you were refering here: #4414

https://discord.com/channels/595666850260713488/598292067260825641/1388206313116270764

Any more ideas of changes that we should do at every fork?

[jtraglia]

The tests & templating look really good @leolara.

I'm just unsure of the templating tests. I would prefer we delete those.

[jtraglia]

Hmm yeah I don't know about this file. I get that these were probably useful when developing the test templating, but this isn't something I want to maintain in the future. I wouldn't have time to properly review this either. Tests for the test framework feels a bit unnecessary to me as well. Let's delete this file.

[leolara]

@jtraglia Regarding the unit tests of the templating system, STEEL adds unit tests for test infrastructure. Perhaps I have added too many tests, as perhaps AI makes it to easy. So what other people in STEEL suggested is to reduce the number of tests, to a few basic ones and a few corner cases.

[jtraglia]

@jtraglia Regarding the unit tests of the templating system, STEEL adds unit tests for test infrastructure. Perhaps I have added too many tests, as perhaps AI makes it to easy. So what other people in STEEL suggested is to reduce the number of tests, to a few basic ones and a few corner cases.

Sorry, I still want to delete the file.