Provide option to automatically add specific directories/files to .gitignore

[jthomasmock]

Positron Version: 2023.09.0 (Universal) build 203

Steps to reproduce the issue:

1. Create a folder and add a virtual environment
2. Initialize a git repo from source control menu
3. Get warning that there are too many files since the entirety of the venv is included and not automatically git ignored.

What did you expect to happen?

I would like to be able to ignore specific files/directories by default or right-click to ignore that directory.

There was an ignored? feature request for this: microsoft/vscode#107521

Were there any error messages in the output or Developer Tools console?

[jthomasmock]

It looks like future versions of Python may also add a .gitignore file to Venv: python/cpython#108125

[jthomasmock]

uv venv does this by default 🚀 which is really nice!

They add a gitignore with * inside of the .venv folder.