Controls
• Click / Tap: drop a Cue (near particles flash + brighten)
• Space: random Cue
• Random Door Walls: random barriers with 1 guaranteed “door gap” each (soft repulsion field)
• Clear Walls: remove all walls

Associatron-ready visual hooks (no coupling yet)
• p.intensity (0..1): “context-match brightness” (slow fade)
• p.isCueHit: short “Spark” flash (TTL)
• p.isRecallCore: warm tint on “winner core” (placeholder)