Phase 2: Station card UI with artwork

[KevinTCoughlin]

Display station artwork in saved stations list with visual cards.

What:

• Fetch artwork from radio-browser.info for each station
• Display in cards with image, station name, stream info
• Extract dominant color from image for accent
• Tap card to play, long-press to edit

Why: Visual design matches Transistor, improves discoverability and UX.

Implementation:

• Add imageUrl field to RadioBrowserStation
• Fetch and cache images via Glide
• Extract dominant color using Palette API
• Update SettingsSheet to show station cards
• LazyVerticalGrid layout

Reference: Transistor CollectionAdapter.kt (station card design with images)

Phase: 2 (UX Polish) | Effort: 15-18h | Target: feature branch