An Azure service that is used to implement corporate governance and standards at scale for Azure resources.
Hello Patrick.
Welcome to MS Q&A
Since Microsoft.App has remained in the Registering state for over 24 hours despite multiple registration attempts, this appears to require investigation from Microsoft Support.
Please ask Microsoft support to check the provider registration status at the subscription level and reset or complete the registration if needed. The additional issues with Azure CLI sign-in (error 530035) and ACR Tasks may also need to be investigated separately to determine whether they are related.
As the portal and Cloud Shell are accessible, please continue troubleshooting through Cloud Shell while awaiting support. Share the subscription ID and relevant error details through the support case for further investigation.
Thanks.
Deepanshu