feat: use js sdk v3 - Githubissues

Updated the snippet to the latest SDK v3. Also, I removed the support for legacy SDK as it's not required anymore.

Type of change

[ ] Bug fix (non-breaking change which fixes an issue)
[x] New feature (non-breaking change which adds functionality)
[x] Breaking change (fix or feature that would cause existing functionality to not work as expected)
[ ] This change requires a documentation update
Checklist:
[x] My code follows the style guidelines of this project
[x] I have performed a self-review of my own code
[x] I have commented my code, particularly in hard-to-understand areas
[-] I have added unit tests for the code
[-] I have made corresponding changes to the documentation