The slideshow reaches a real Apple TV

The slideshow is running on a real Apple TV and showing media from my actual Photos library. That changes the nature of the work: I can now judge it from the couch, with the Siri Remote, against the photos and videos it is meant to live with.

Changelog

• Apple TV Slideshow now runs on real Apple TV hardware and can present photos, videos, and Live Photos from the Photos library.
• First-run permission and remote-guide screens now focus and respond predictably to the Siri Remote, including Back behavior.
• Text, panels, and buttons now stay readable in both light and dark Apple TV appearances.
• Photos Source settings now omit the Library selector when Apple TV exposes Personal and Shared Library items only as one combined collection.
• Provider settings now show choices only when those choices are genuinely selectable.
• Added an optional Date Overlay that shows when each photo, video, or Live Photo was captured.
• Dates use a compact, readable bottom-right design with the year given stronger visual emphasis.
• Date Overlay starts turned off and can be enabled under Playback settings.
• Added an optional Location Overlay that turns available photo and video GPS metadata into recognizable place names.
• Locations use a clean two-line bottom-left design that remains readable over varied media.
• Location Overlay starts turned off and quietly hides itself whenever a place cannot be resolved.