Fix 6 bugs in test/setup_lab.sh; update session log
Bugs fixed (all in test/setup_lab.sh):
A. unset P4CONFIG at top -- SDP shell env was overridden by .p4config.local
B. load_checkpoint.sh arg order: file first, then -i N -y
C. Phase 6 idempotency: check live p4d connectivity, not server.id file
D. Phase 10 same idempotency fix -- check p4d responds as standalone
E. Phase 10: p4login before p4 configure unset auth.id (auth required first)
F. Phase 7: add p4login -v 1 for perforce user (needed before Phase 9 p4verify)