Merge Connected and Candiate

These 2 concepts are largely overlapping, so get rid of candidates,
and use the more general connected bonus.

STC:
LLR: 2.96 (-2.94,2.94) [-4.00,0.00]
Total: 27118 W: 5748 L: 5689 D: 15681

LTC:
LLR: 2.95 (-2.94,2.94) [-4.00,0.00]
Total: 20105 W: 3667 L: 3579 D: 12859

bench 6919463