Loose grains and solid ground look different: a seam on the rock, pebbly lighter grains (t33)

- Smooth look: natural ground gets a soft seam where loose grains meet it; packed grains keep a
  pebble texture and are slightly lighter. Pixel look and thermal lens: the same idea per pixel.
- play.py: the F-on-a-mold toast check records toasts the key press makes instead of counting
  the ones on screen, which failed when an older toast expired at the same moment.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/PROJECT_MAP.md

@@ -356,7 +356,7 @@ Drawing (src/render/): browser only. This file: the renderer state R, colour tab
 Propagated coloured light from glowing and burning cells.
 - functions: builtForLight, computeLight
 
-### src/render/world.js (308 lines)
+### src/render/world.js (321 lines)
 Scale colour without changing the smooth-look class.
 - functions: fogColor, drawWorld
 - variables: TUBE_CLASS
@@ -374,7 +374,7 @@ Smooth look: WebGL setup, texture uploads, drawing and adaptive resolution.
 - functions: smCompile, smoothAvailable, smUpload, smoothDraw, smoothPace
 - variables: SM, smBytes
 
-### src/render/smooth-shaders.js (325 lines)
+### src/render/smooth-shaders.js (330 lines)
 Smooth shaders: vertex and fragment programs for the rounded world look.
 - variables: SM_VS, SM_FS
 
@@ -543,3 +543,4 @@ The frame loop and boot.
 - `tools/scenes/mold-labels.js`: Run after clear-sky.js: filling, blocked, set, and hot machinery in one view.
 - `tools/scenes/silo.js`: Run after clear-sky.js; leave paused so the open gate keeps its demonstration charge.
 - `tools/scenes/stone-uses.js`: The stone and sand machines: a half-full silo with its gate open over a belt, a stone cutter fed with rubble, and cut stone and glass brick walls. Run clear-sky.js first, e.g. python3 tools/shot.py /tmp/stone.png --setup tools/scenes/clear-sky.js --js "$(cat tools/scenes/stone-uses.js)" --ticks 240 --zoom 7
+- `tools/scenes/t33-ground.js`: Paused dug pocket: copper ore, rubble and dirt against stone, granite and dirt. Use --js "..." to set daylight or R.lens after this setup; CAM frames the pocket.