Create a Development Container Feature for Dev Proxy

[garrytrinder]

To make it easier for developers to integrate Dev Proxy into GitHub Codespaces and VS Code Dev Containers, we should create a Development Container Feature for Dev Proxy.

Benefits of this approach:

• Streamlined setup: Developers can enable Dev Proxy with a single line of configuration in their devcontainer.json, avoiding manual installation steps.
• Consistency: Ensures consistent Dev Proxy installation and configuration across different environments and teams.
• Reusability: The feature can be reused across multiple dev containers and projects, reducing duplicate effort.
• Discoverability: Features are listed in the Dev Container Feature marketplace, making Dev Proxy easier to find and adopt.
• Best practices: Follows the recommended approach for extensibility in Codespaces and Dev Containers.

A GitHub repository template is available to author the feature: @devcontainers/feature-starter

VSCode Docs: Dev Container Features

[waldekmastykarz]

Cool idea! Let's spec it out some more so that we know what we'd like to have.