feat(rpc): implement Filecoin.NetAutoNatStatus

[hanabi1224]

Summary of changes

Changes introduced in this pull request:

• implement Filecoin.NetAutoNatStatus

     Running `target/debug/forest-tool api compare --filter NetAuto`
| RPC Method                | Forest | Lotus |
|---------------------------|--------|-------|
| Filecoin.NetAutoNatStatus | Valid  | Valid |

Reference issue to close (if applicable)

Closes

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation,
• I have added tests that prove my fix is effective or that my feature works (if possible),
• I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.

[LesnyRumcajs]

Should there be an entry in the changelog?

[lemmih]

Should there be an entry in the changelog?

I'm okay with not having a changelog entry for each RPC method. Instead, we'll have an entry for each RPC milestone (full v0, full v1, full lotus compliance, etc).