[Feature]: Remember nix environment answer

[yajo]

Is your feature request related to a problem? Please describe.
Every time I switch to a direnv-enabled workspace, I get this message:

Describe the solution you'd like
The extension should ask only the 1st time a workspace is opened, and remember the answer for next times.

Describe alternatives you've considered
Sometimes I just ignore it. It seems to work anyway. But I'm not sure if it has any side effects.

Additional context
My .envrc files usually contain just use nix or use flake.