fix: added GenVM decoder to readContract method

[cristiam86]

Fixes #40

What

• Added the GenVM decoder to the result obtained from the readContract method

Why

• To allow developers to get the decoded data when calling an Intelligent Contract method

Testing done

• Tested in the GenLayer Boilerplate project

Decisions made

The same decoder that is currently working in the GenLayer Studio has been added.

Checks

• I have tested this code
• I have reviewed my own PR
• I have created an issue for this PR
• I have set a descriptive PR title compliant with conventional commits

Reviewing tips

Check that calling a contract read method, now returns a decoded object.

User facing release notes

Read contract data has been decoded so its value can be used

[AgustinRamiroDiaz]

@cristiam86 can you add the example on how to decode on the frontend side?

https://github.com/yeagerai/genlayer-project-boilerplate/blob/3b40f5389c9b867d613fafe7772bc0dcb5e5bdc4/app/src/logic/PredictionMarket.js#L18-L38

[AgustinRamiroDiaz]

I'm approving to unblock dKOL, but

• I don't feel qualified to review this
• It'd be nice to have e2e tests for this

[AgustinRamiroDiaz]

I've also created #44 somewhat related