Improve Azure local provisioning: detect and facilitate first time login, show credential choices

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

Today, Aspire assumes that the user is already logged into Visual Studio, VS Code, or Azure CLI for Azure local provisioning. The current experience does not detect which of these mechanisms (if any) are available, nor does it facilitate login or provide a UI for the user to choose their preferred credential provider. There is a configuration option for selecting a credential provider, but this is not surfaced in the user experience.

**Describe the solution you'd like**

1. Detect available credential providers in the user's environment (VS, VS Code, az cli, etc) and present the user with a choice of which to use for login.
2. If no login mechanism is detected, proactively facilitate or guide the user through the login process for one of the supported providers.
3. Surface the credential provider configuration option in a user-friendly way.

**Additional context**
Improving this experience will make the first-time Azure login in Aspire smoother and more intuitive, especially for new users.

cc @eerhardt