Improve discovery flow for Squeezelite

[peteS-UK]

Proposed change

When the Squeezebox integration is added, it searches the network for LMS. This PR incorporates the show_progress form whilst the discovery is underway. If nothing is discovered, the flow goes directly to a manual form. If a server is discovered, the flow uses a menu to offer to configure the discovered LMS or a different one. If the discovered LMS is chosen, then flow tests connectivity using default options, and if these allow connection, the config entry is created without needing to display a form.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @rajlaud, @pssc, mind taking a look at this pull request as it has been labeled with an integration (squeezebox) you are listed as a code owner for? Thanks!

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[github-actions]

There hasn't been any activity on this pull request recently. This pull request has been automatically marked as stale because of that and will be closed if no further activity occurs within 7 days.
If you are the author of this PR, please leave a comment if you want to keep it open. Also, please rebase your PR onto the latest dev branch to ensure that it's up to date with the latest changes.
Thank you for your contribution!

[peteS-UK]

bump