refactor: switch gas report parsing from RST to native JSON output

[Lil-Duckling-22]

Replace RST parsing with native JSON output to remove fragile regex-based parsing.

Fixes #16373

[github-actions]

Thank you for your contribution to the Solidity compiler! A team member will follow up shortly.

If you haven't read our contributing guidelines and our review checklist before, please do it now, this makes the reviewing process and accepting your contribution smoother.

If you have any questions or need our help, feel free to post them in the PR or talk to us directly on the #solidity-dev channel on Matrix.

[ArturInspector]

rst is pain this pr would be cool

[Lil-Duckling-22]

rst is pain this pr would be cool

thanks, ill try to solve this, but ill need probably a little bit more time to fix potential ci's

[ArturInspector]

One test bud). let's get in touch, I liked your zk vm projects )