Train widget: the app's own train map instead of the old diagram

[intelarc]

The Ngā Tereina widget now shows the same map as the Trains tab's Diagram view, instead of the old schematic.

• New TrainArt: renders the map off screen at the widget's size with MapLibre's MapSnapshotter. The map runs edge to edge under a shaded header. It shows:
  • the quiet dark basemap
  • the lines along their real tracks, side by side where they share rails
  • station dots, platform bars and ranked names
  • every train snapped to its own line, with a late dot when it's running late
• Shared with the app:
  • drawLayers is split into aklLayers / aklData
  • the line and station building moves into TrainNet.lines / TrainNet.stopsAndLinks
  • so the widget and the Trains tab draw from the same code
• Real tracks cached: TrainNet.geo(ctx) saves the real tracks to rail-track.txt, so the widget can draw them when the timetable isn't loaded.
• Fallback: if the map can't be drawn, the widget falls back to the old diagram.

🤖 Generated with Claude Code

https://claude.ai/code/session_011C2fAvFFcMRkaF7qSvRA1v

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Generated by Claude Code