chore: refactor get legacy providers

[RyukTheCoder]

Summary

In some places we used separateLegacyAndHubProviders without any config to access only legacy providers which was unsafe and produced some issues after removing the experimentalWallet config. It is fixed by defining a seperate function for accessing legacy providers.

Checklist:

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• Implemented a user interface (UI) change, referencing our Figma design to ensure pixel-perfect precision.

[yeager-eren]

lgtm