Config flow and HA compatibility fixes

This release fixes several Home Assistant compatibility issues:

• Polling interval selection now uses a dropdown instead of radio buttons, preventing config flow submit errors.

• The deprecated ScannerEntity import has been updated for future Home Assistant Core versions.

• Legacy names such as "" are automatically cleaned up to the original name.

Other changes

• Fix config flow polling selector and HA compatibility warnings (#531) @dkwolf1
• Fix pre-commit formatting after PR #527 (#528) @dkwolf1
• Fall back to global client_list query when per-node returns 5xx (#527) @ericmason

📦 Dependencies

• Bump ruff from 0.15.16 to 0.15.17 (#530) @dependabot[bot]