VSCode dev container not set up to run all unit tests locally

[kdowney-lot49]

Describe the bug
About 20 out of the unit tests reliably fail inside the dev container due to differences between the CI environment and the one prevailing inside the dev container.

Pants version
N/A, observed on main

OS
Inside Debian 12 "bookworm" container running on MacOS ARM64 but I believe this to apply to any host.

Additional info
The base Rust image from Microsoft is a relatively old Debian build, which makes it difficult to address some of the other gaps. This PR will upgrade the base and then separately install Rust to reduce complexity or working around the various environment normalization issues.

[kdowney-lot49]

@benjyw related to our conversation on previous PR, will keep this change separate so dev team can assess if it's worthwhile.