ci: added license, fix npm publish

[fadeev]

Publishing on npm failed:

https://github.com/zeta-chain/protocol-contracts-solana/actions/runs/10958248436/job/30428068789

I think this is because metaDAOproject/setup-anchor doesn't specify the npm registry when setting up npm:

https://github.com/metaDAOproject/setup-anchor/blob/087a07cc86e8adcca657b9aaf0af9d5d4c504871/action.yml#L22-L24

And GH docs say one should do it:

Please note that you need to set the registry-url to https://registry.npmjs.org/ in setup-node to properly configure your credentials.

Also, added a license.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 11.65%. Comparing base (5ef421e) to head (f12fd3a).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #31   +/-   ##
=======================================
  Coverage   11.65%   11.65%           
=======================================
  Files           1        1           
  Lines         163      163           
=======================================
  Hits           19       19           
  Misses        144      144           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[fadeev]

@CharlieMc0 please, review.

[lumtis]

LGTM