Chore/cosmos exec condition

[genaroibc]

Description

Add optional param useBroadcast to executeRoute() and executeRouteCosmos() methods.
When useBroadcast: true, executeRouteCosmos() uses signer.signAndBroadcast() instead of signer.sign() to sign transactions.

The purpose of this is that we are integrating Nomos, a multisig provider, and they reserve sign() for apps to verify user signatures, but instead override signAndBroadcast() to include their custom logic.

This PR also changes how we determine whether to use executeRouteEvm() or executeRouteCosmos().
Now it parses fromChain from route params. If fromChain is a number, use executeRouteEvm(). If not, use executeRouteCosmos().

Type of change

• New feature (non-breaking change which adds functionality)
• Refactor (code improvement)

How Has This Been Tested?

Please describe the steps to test.

Evidence

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Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules