Add publish/restoreREnv events to VSCode extension

[sagerb]

Intent

This PR adds support for the "Restoring R Environment deployment phase"

Resolves #1660

Type of Change

• • [ ] Bug Fix
• • [x] New Feature
• • [ ] Breaking Change
• • [ ] Documentation
• • [ ] Refactor
• • [ ] Tooling

Approach

I basically replicated the python restore events and handlers. When deploying R Content, the log messages are handled and displayed in a new log section, as seen here below:

Automated Tests

Directions for Reviewers

Please validate the functionality when publishing an R project as well as a non-R project.

Checklist

• [ ] I have updated CHANGELOG.md to cover notable changes.

[mmarchetti]

Validated with R and non-R content.