Print activation instructions for a venv after one has been created

[0v00]

Summary

• Add prompts for users to activate the .venv after it has been created.
• Closes uv venv does not suggest how to activate #1326

If the platform os matches Os::Windows then we provide the following prompt:

writeln!(
   printer,
   "Activate with .\\{}\\Scripts\\activate.ps1",
   path.normalized_display().cyan()
)

Otherwise we provide the following prompt:

writeln!(
  printer,
  "Activate with source {}/bin/activate",
  path.normalized_display().cyan()
)

I've added additional filters in crates/uv/tests/venv.rs so there shouldn't be issues on any of the CI runs (not sure what some of the Windows paths could look like, so these filters might need to be changed):

        (
            r".*?\\\.venv\\Scripts\\activate\.ps1", 
            "Activate with source /home/ferris/project/.venv/bin/activate"
        )

Test Plan

• Ran tests in crates/uv/tests/venv.rs and updated snapshots.
• Ran uv venv in a Docker container to test that the output is correct (running Ubuntu)

[T-256]

what about cmd users?

• Add CMD support #1523

[zanieb]

I wonder if we can detect the current terminal type in Windows...

[zanieb]

(or if we should just show both?)

[0v00]

I'm also not sure if we can correctly/reliably detect the current terminal type in Windows, I've added in the below prompt:

Activate with:
- Powershell: .\.venv\Scripts\activate.ps1
- CMD: .\.venv\Scripts\activate.bat

and updated filters and snapshots

[zanieb]

@AlexWaygood / @MichaReiser can you take over review of this?

[AlexWaygood]

I believe typing .venv\Scripts\activate (omitting the file extension) should actually work on both PowerShell and CMD. (It does on my Windows machine!) If we just suggested doing that, it woudl avoid us having to figure out how to detect which Windows shell the user is using (and it's also fewer characters to have to type out ;).

If you're on CMD, it'll naturally pick up the .bat file; if you're on PowerShell, it'll naturally pick up the .ps1 file

[0v00]

Thank you, that definitely helps make the prompt a lot cleaner/simpler. Have updated it.

[AlexWaygood]

LGTM, thanks!

[AlexWaygood]

I tested locally with zsh on my mac, CMD on my Windows PC, and PowerShell on my Windows PC. All looked good!