Venues: persistent room, motivated camera, ride; drop Pylon Grid

- Venue as one continuous place: persistent per-song layer, interpolated
  venueState, story jumps (one re-hang max + recap) with camera cuts
- Room camera shot plan (venueShots.js): per-section size/target, monotonic
  look sweep, traverse glide body, room-side alternation
- New Ride venue: generated vehicle + actor passengers, radio RTT screen,
  chase/stationary modes, ride archetype across generator/camera/staging
- Flora cost trim (5x(12+6+6) -> 4x(8+4+4) SDF evals, 204ms -> 140ms worst)
- Delete Pylon Grid shader (2.5s/frame SwiftShader); drop its metadata row
- tools/venue-check.js headless gate harness + venue-gallery explorer

flow-state/vite.config.js

@@ -303,6 +303,7 @@ export default defineConfig({
                 debug: resolve(process.cwd(), 'debug.html'),
                 gallery: resolve(process.cwd(), 'gallery.html'),
                 filmstrip: resolve(process.cwd(), 'filmstrip.html'),
+                'venue-gallery': resolve(process.cwd(), 'venue-gallery.html'),
             },
         },
     },