`--override-input` ignores local registries and falsely warns about using registry entries as flake inputs

[getchoo]

Describe the bug

Instead of respecting my locally configured registries, Determinate Nix will only use the registry to resolve the nixpkgs in nix build --override-input nixpkgs nixpkgs. It also gives me the deprecation warning for #37 when the current flake is not actually affected by it

Steps To Reproduce

1. Try to override the input of a flake with a local registry entry
2. See the global registry entry being used instead
3. See the warning about using registry entries as flake inputs, even if you aren't

Expected behavior

--override-input respects my local registry, and Determinate Nix does not give me false deprecation warnings

Metadata

Determinate Nixd daemon version: 3.8.5
Determinate Nixd client version: 3.8.5

You are running the latest version of Determinate Nix.

The feature lazy-trees is enabled. Visit https://dtr.mn/lazy-trees to opt out or for more information

nix (Determinate Nix 3.8.5) 2.30.2

Additional context

This was reported upstream in NixOS#13144 and fixed after NixOS#13284. However, going back to the first Determinate Nix release that PR showed up in (via nix shell https://flakehub.com/f/DeterminateSystems/nix-src/3.6.7) shows that this fix never actually had an effect here

Checklist

• checked latest Determinate Nix manual (source)
• checked open bug issues and pull requests for possible duplicates