ST_G (single-block G) and ST_H (multi-block H(ek)) are disjoint FSM phases, so one sha3_top serves both: mb_en and ready_i are phase-muxed, h_hash/h_vo alias the shared core's outputs. Removes the dedicated u_sha3_h instance and its keccak_core. 11/11 KAT PASS (K=2 c0-4, K=3/4 c0-2), byte-exact, 0 file-not-found.