Lists the egress the build assumes (Go module proxy, toolchain download, raw.githubusercontent for golangci-lint, github for non-proxied modules) and the runtime assumes (LiteLLM gateway, brain-mcp, YouTube/Vimeo APIs, per-user BYO-AI hosts only on opt-in), so a locked-down koala act_runner or dev env knows what to allow or which GOPROXY to set. Notes the claude.ai sandbox allowlist is separate and unrelated.