Docs-only appendix per ADR-0011 (never a shipped artifact). The three mandatory ALB attribute overrides (idle_timeout=4000, client_keep_alive=604800, preserve_host_header=true) with the telephony reasons; the never-NLB-TLS rule with the 350s-silent-drop + no-HTTP- context rationale; 100-target-group fleet ceiling; per-node EIPs for direct media UDP; copy-paste aws elbv2 CLI path to first call. Signed-off-by: Aaron D. Lee <himself@adlee.work>