How to pass a dynamic parameter to the auth endpoint?

**Is your feature request related to a problem? Please describe.**
I use a custom auth provider. They support passing a login_hint parameter to pre-populate the user's email address. This is extremely helpful for offering easy login links for users from emails or other platforms. Is there no way to pass a dynamic parameter to the ./auth/login/[provider] endpoint?

**Describe the solution you'd like**
I would like to be able to pass dynamic parameters to the login page.

**Describe alternatives you've considered**
I would also be open to being able to link to my auth provider login page directly, which allows me to pre-populate the email. It appears that my session is not authenticated when it routes back to my application though. Looking at the network activity in my browser during a login, I'm assuming this is due to the reliance on the staticWebAppsAuthNonce value.

Any thoughts would be greatly appreciated!