Avoid panic for non-UTF-8 virtualenv paths

[konstin]

A non-UTF-8 uv venv destination currently panics while generating activation scripts. Return a clear error at the activation-script conversion site instead.

[zanieb]

Why does a virtual environment path need to be utf-8? Just for the activation scripts? I am unsure that should error?

[konstin]

We assume that our paths are UTF-8 serializable, so that we can use the location in UTF-8 files, which is why this code previously panicked; This isn't the first non-UTF-8 error variant we're adding.

[woodruffw]

Probably too large of a change for just this PR, but maybe we can use camino for the subset of path operations that we want to enforce UTF-8 on? I think the APIs/error states it provides are pretty ergonomic.

(OTOH, it's another dep.)

[astral-sh-bot]

uv test inventory changes

This PR changes the tests when compared with the latest main baseline.

• Added tests: 1
• Removed tests: 0
• Changed suites: 1

uv::python: +1 / -0

Added:

• uv::python::venv::non_utf8_path

Removed: none

[konstin]

camino would be nice, but it would require changing almost all of the path handling we do.

[konstin]

Regarding regression safety: This turns an existing panic in _ => escape_posix_for_single_quotes(location.simplified().to_str().unwrap()) into an error.