Having a single blake3 store path from a one-time trial breaks things

[grahamc]

Describe the bug

Essentially any store path that used blake3 taints the system if you don't keep the feature on.

Steps To Reproduce

1. Have a blake3 store path
2. Run nix path-info --json --all
3. Witness the error: error: experimental Nix feature 'blake3-hashes' is disabled; add '--extra-experimental-features blake3-hashes' to enable it

Note you also can't delete that path:

grahamc@Grahams-MacBook-Pro nix-src % nix-store --delete /nix/store/pym15ihqmch7c9l45zxwf20r2drfj97p-oh-no-a-hash-mismatch2
finding garbage collector roots...
0 store paths deleted, 0.00 MiB freed
error: experimental Nix feature 'blake3-hashes' is disabled; add '--extra-experimental-features blake3-hashes' to enable it

And actually, passing that flag to the delete command doesn't actually work:

grahamc@Grahams-MacBook-Pro nix-src % nix-store --delete /nix/store/pym15ihqmch7c9l45zxwf20r2drfj97p-oh-no-a-hash-mismatch2 --extra-experimental-features blake3-hashes
finding garbage collector roots...
0 store paths deleted, 0.00 MiB freed
error: experimental Nix feature 'blake3-hashes' is disabled; add '--extra-experimental-features blake3-hashes' to enable it

...because you need sudo :)

grahamc@Grahams-MacBook-Pro nix-src % sudo nix-store --delete /nix/store/pym15ihqmch7c9l45zxwf20r2drfj97p-oh-no-a-hash-mismatch2 --extra-experimental-features blake3-hashes
warning: $HOME ('/Users/grahamc') is not owned by you, falling back to the one defined in the 'passwd' file ('/var/root')
finding garbage collector roots...
deleting '/nix/store/pym15ihqmch7c9l45zxwf20r2drfj97p-oh-no-a-hash-mismatch2'
deleting unused links...
note: currently hard linking saves 0.00 MiB
1 store paths deleted, 0.00 MiB freed

Expected behavior

A user should be able to introspect their database and also delete paths, even if an experimental feature was needed to create that path.

Metadata

grahamc@Grahams-MacBook-Pro nix-src % nix-env --version
nix-env (Determinate Nix 3.8.2) 2.30.1

Checklist

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

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