Update Core- & Integration-APIs for Remote 3

[zehnm]

Remote Two and Remote 3 share the same APIs. New features in Remote 3 are optional and can be retrieved with feature flags.

• change Remote Two naming to UC Remote, to include also Remote 3.
• Include model_number in public version information.
• Initial RGB button backlight configuration.
  • Static color backlight configuration for all or specific zones. No individual color per zone yet. This can be added later.
  • Define backlight zones in button configuration metadata.
• Wireless charging: metadata, temporarily enable & disable.