Support for devcontainer.json Files Outside of Repository with `gh cs create --devcontainer-path`

[shinychimra07]

Describe the feature or problem you’d like to solve

Currently, the gh cs create --devcontainer-path command is designed to work with devcontainer.json files that are located within the repository(https://github.com/cli/cli/blob/0f2e1ed9d19f73d20eb0dd124f4b5cba3111f2e9/pkg/cmd/codespace/create.go#L229). However, there are use cases where it would be beneficial to support devcontainer.json files located outside of the repository directory.

This feature would enable greater flexibility and convenience, especially in scenarios where:

• The devcontainer.json is shared across multiple projects.
• Users want to maintain a centralized location for their dev container configurations.

Proposed solution

Enhance the gh cs create --devcontainer-path command to accept a path to a devcontainer.json file located outside of the repository directory. This could involve:

• Path Validation: Ensure the specified path is valid and points to a proper devcontainer.json file.
• Relative and Absolute Paths: Support both relative and absolute paths (e.g., https://raw.githubusercontent.com/.../devcontainer.json) to the devcontainer.json file.

How will it benefit CLI and its users?

• Consistency: Ensures all team members use the same development environment.
• Efficiency: Reduces redundancy by centralizing the configuration file.
• Flexibility: Simplifies managing and switching between different container configurations.

[shinychimra07]

CC: @craiglpeters @nithinmichael