* Added M3 demo app
* Changed to use the centralized lint configuration.
* Moved the app at the root level
* Added to CI
* Added app to beta CI and commented app on stable CI file
* Update README.md
* Addressed comments
* fixed comments
* Reverted app name in CI files.
* Added project to the Pub Dependabot config
* Linting pass for current beta channel standards
Co-authored-by: Qun Cheng <quncheng@google.com>
Co-authored-by: Craig Labenz <craig.labenz@gmail.com>
