✨ Feature Request: Add support for `--detached` mode in `balena push`

[nilsdebruin]

Is your feature request related to a problem? Please describe.

Currently, when using this action in a GitHub Actions workflow, the job step waits for the entire Balena Cloud build to complete before proceeding. For long-running builds, this can significantly increase the duration of the CI/CD pipeline and occupy a GitHub runner for the entire build time.

The Balena CLI's balena push command has a --detached (-d) flag that is designed to solve this exact problem. It starts the build on Balena's servers and then immediately returns the release ID and exits, allowing the CI job to complete quickly.

Describe the solution you'd like

I would like the deploy-to-balena-action to expose the --detached flag from the Balena CLI. This would allow users to trigger a build without waiting for it to finish.

A new boolean input, perhaps named detached, could be added to the action.yml.

Example action.yml input:

inputs:
  # ... existing inputs
  detached:
    description: 'Start the build and exit without waiting for completion (equivalent to balena push --detached)'
    required: false
    default: false

### Describe alternatives you've considered

The only alternative is to run `balena push` manually in a `run` step within the workflow, but this defeats the purpose of using this dedicated and well-maintained action.