* Refactor login_page with a _showSnackBar function
* Add an onError block to onAuthStateChange
Errors get swallowed without this error handler, I noticed it when I had requested too many magic link emails, there was no feedback in the ui, nor in the logs in the console.
* Fix SnackBars not being displayed and add a _showSnackBar function
* Fix code samples for login_page.dart and account_page.dart to reflect fixes in #27104
* Fix isError not being passed for an Unexpected Error in login_page
* Update flutter user management example to a more modern code
* Update the guide to match the new content
* run formatter
* got rid of excess code and minor format fix
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Co-authored-by: dshukertjr <dshukertjr@gmail.com>
* update flutter quick start and example app to use flutter v2
* update examples and blog articles to use Flutter SDK v2
* fix versions used in examples
* update image picker to 1.0.5
* minor code refactor for sample code
Ivan Vasilov