Generated app icon concepts for `Flights`.

Files:
- `01_orbital-route.png`: dark, route-led, strongest "fly everywhere" story.
- `02_window-badge.png`: bright and premium, centered globe with orbital motion.
- `03_atlas-tile.png`: editorial/lightweight, dark inset tile on an airy base.
- `04_night-ring.png`: bold and futuristic, orbit-ring treatment on a dark field.
- `05_route-card.png`: clean iOS card language using the app's UI motif.
- `comparison-sheet.png`: all five options on one board.

Regenerate:
```sh
swift -module-cache-path /tmp/swift-module-cache design/generate_icon_options.swift
```