Add REQ-106/TEST-108: lane build phase runs with network link off Specify the lane network split chosen as N2 on VITechnologies/projectbuddy#182: fetch steps run with the link on and no secrets; build steps run with secrets and the link off until power-off. Outputs return on a per-run disk read after poweroff (completion channel C1), because any guest process can write a VirtualBox guest property. Update REQ-090 (per-phase argument vectors and timeouts; CodeRef now cites scripts/lane/declaration.py), REQ-092 (per-phase evidence), REQ-093 (build-phase-only secrets), SYS-REQ-027 allocation, and SRS/RTM/test lists. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>