Flight selection and improved approach calculations

New Features

• Flight Selection Toggle: Toggle flight selection directly from the flight list.
• Styling for Selected Flights: Adds subtle styling to highlight selected flights on the radar.
• Receding Flight: Adds a new boolean is_receding, allowing for identification of flights whose headings deviate less than 60 degrees from the tracker. (Opposite of the existing is_approaching functionality).

Enhancements

• Default Sort Settings: Fixes issues with default sorting settings and updates documentation for clarity.

Full Changelog: v0.0.9...v0.0.10