Add 4 Circom circuits, 4 design docs, update deploy.sh and Makefile for 17 contracts

feat: wire 5 new zk-accountability contracts into deploy.sh

feat: deploy consensus contract alongside verifier/payment/reputation/insurance

Build fleet_learning in deploy.sh; document its constructor-arg deploy once a verifier + reward token exist

chore(deploy): build bn254_verifier and document its VK-dependent deploy step

deploy: add fleet_identity contract (constructor: admin + tree depth)

feat(deploy): testnet deployment script for all four contracts