Where code goes in Venus, engine vs game. Use BEFORE writing or placing any rendering/lighting/physics/streaming feature, when reviewing a diff that adds engine-shaped code to src/neon, src/wyrdholm, src/networked_rts, src/demo or examples/, or when deciding whether to promote game code into the engine. Encodes the standing centralisation rule (Ben, 2026-08-14), the LOOK-vs-MECHANISM test, the promotion checklist, and the red-flag list from the 2026-08-14 audit.
