Add `getPublicKeyFromOutput()` to `Transaction` class

[theanmolsharma]

Add the following function to Transaction class

getPublicKeyFromOutput(index: number): Buffer | null {}

This function should extract the public key from the output script. The following output script types contain public key in script:

• P2PK
• P2TR

For all other script types, the function should return null.

[rajarshimaitra]

For all other script types, the function should throw an error.

This seems like an Option case than a Error case, as most other script types won't hold SPs. Is there a way to do Options in JS?

[theanmolsharma]

For all other script types, the function should throw an error.

This seems like an Option case than a Error case, as most other script types won't hold SPs. Is there a way to do Options in JS?

I think we can set the return type to Buffer | null