[Enhancement] Add alert when connecting to server if user ID is not a UUID

[nichwall]

Describe the Feature/Enhancement

To better notify users that they are still connecting with an old user ID (username instead of UUID, as discussed in #1401), there should be a pop-up of some kind to notify users.

The popup only needs an "OK" button, and should happen every time a user signs in to the server so they don't miss it, but not so annoying that they have to update the connection immediately. This will also help address the issue of users who only stream since they would not see the warning about progress not being synced prior to the change.

Why would this be helpful?

Communicate a planned change requiring user action prior to change taking place.

Future Implementation (Screenshot)

Popup could say:

"You originally set up the connection to this server prior to the database migration in 2.3.0, released June 2023. A future server update will remove the ability to sign in with this old connection. Please delete the existing server connection and connect again (use the same IP, username, and password). If you have any downloaded media on this device, the media will need to be downloaded again to sync with the server."

A "Learn More" button can link to #1401 or another description of the problem.

Audiobookshelf App Version

Android App - 0.9.77

Current Implementation (Screenshot)

An example of what the popup could look like from the app settings.