Refactor to paymaster url & added check for chain ids + tests

[VGabriel45]

Summary

Refactor to paymaster url & added check for chain ids + tests. This will introduce a breaking change, paymasterUrl will be used over biconomyPaymasterApiKey.

Change Type

• [ ] Bug Fix
• [x] Refactor
• [ ] New Feature
• [x] Breaking Change
• [ ] Documentation Update
• [ ] Performance Improvement
• [ ] Other

Checklist

• [x] My code follows this project's style guidelines
• [x] I've reviewed my own code
• [x] I've added comments for any hard-to-understand areas
• [ ] I've updated the documentation if necessary
• [x] My changes generate no new warnings
• [x] I've added tests that prove my fix is effective or my feature works
• [x] All unit tests pass locally with my changes
• [ ] Any dependent changes have been merged and published

[linear[bot]]

SMA-675 Refactor biconomyPaymasterApiKey to paymasterUrl in SDK

[livingrockrises]

I didn't get rationale behind this change? wasn't this devx abstraction improvement?

[livingrockrises]

also conflicts..

[joepegler]

I didn't get rationale behind this change? wasn't this devx abstraction improvement?

It didn't turn out to be, we've noticed a bunch of users mistakenly assuming their paymaster api key works across different chains. It's what I would have expected too. Given that the chain comes baked into the url, this change makes it plain to devs that paymaster urls don't work cross-chain, and in this PR we now throw an error when we detect a dev attempting this.