Add JSDoc comments to all SharpyClient public methods

[MarcusDavidG]

All public methods on SharpyClient lack JSDoc documentation. Adding @param, @returns, and @throws comments will improve DX for SDK consumers and enable IntelliSense in editors.

[MarcusDavidG]

affa I don assign you this issue.

sdk — Add JSDoc comments to all SharpyClient public methods: #19

fork the repo first before making any changes, then open a PR referencing the issue number.

Org: https://github.com/stellar-sharpy
SDK repo: https://github.com/stellar-sharpy/sharpy-sdk
Contributing guide: https://github.com/stellar-sharpy/sharpy-sdk/blob/main/CONTRIBUTING.md

hit me up if you need any info but everything dey here