Create a server version warning that is displayed when users attempt to use an outdated server

[1hitsong]

This request respects the following points:

• This request is not already on GitHub (I've searched it).
• I agree to follow Jellyfin's Code of Conduct.

Problem Description

Based on feedback from the 3.0.0 release, there are still a lot of users running and connecting to pre-10.9.0 servers. Due to changes in API endpoints, such old servers will not work with the Roku client.

Proposed Solution

When a user attempts to connect to an old, incompatible server version, we should display a notification popup instructing them that 1, the Roku client will not work with it and 2, that they need to update to continue using the client.

Alternatives Considered

Waiting for users to ask why it's not working and manually telling them they need to update.

Additional Information

[SenorSmartyPants]

Can the 2.x version of the Roku client be added to the Roku store as a legacy client in some way?

I run a custom JF from that doesn't have a new version available.

[jimdogx]

@SenorSmartyPants Legacy app will be on the Roku store this Tuesday at 10 am Pacific Time.