GAN parity matrix

The transport identifies each GAN protocol generation explicitly. Regrip core treats those protocol IDs through one common session contract while retaining the Gen4/i4 profile specialization.

Generation	Transport protocol	Core profile	Initial state contract	Capture coverage
Gen1	gan-gen1	gan-gen2	facelets, battery	hardware pending
Gen2	gan-gen2	gan-gen2	hardware, facelets, battery	committed transport capture
Gen3	gan-gen3	gan-gen2	hardware, facelets, battery	hardware pending
Gen4	gan-gen4	gan-gen4 for GANi4_*	hardware, facelets, battery	committed redacted profile replay

ganParityMatrix.test.ts enforces profile selection, capability-gated initial commands, normalized battery/move delivery, and disconnect behavior for all four rows. Gen1 and Gen3 still need representative hardware captures before transport-level parity can be called complete; this matrix makes that remaining gap explicit.