Transfer UI behavior and caller identity depend on call topology, not announcements

Transfer UI behavior and caller identity depend on call topology, not whether an agent briefing is spoken. When a “direct” entry point still creates a separate outbound SIP participant and later moves it into the inbound room, disabling the briefing only shortens an attended-transfer workflow; it does not make the call a cold transfer and it preserves the same outbound caller-ID validation/fallback behavior. For an inbound SIP call that must retain the original ANI, use the provider-supported transfer primitive on the existing inbound leg (for example, SIP REFER via LiveKit TransferSIPParticipant), and test that no independent outbound CreateSIPParticipant call occurs. This applies only when the SIP provider supports external REFER/PSTN transfer; failures such as busy or ringing timeout leave the original caller in the room and still need an explicit application policy.