Use devcontainer features

[rdong8]

The following things are currently manually installed in the Containerfile and should be ported to Dev Container Features once an appropriate official equivalent is released:

• brew

The following things are currently installed via brew in the Containerfile and we may or may not want to port them to Dev Container Features once available. Idk if there is any benefit over brew or not.

• uv
• just
• helix