V4.8.5 SAME V4.8.1 SCREEN — INFINITE PERSISTENT ENTRANCES

The Area Transitions / Entrances screen is unchanged from V4.8.1.

Behavior fix:
- Each matching/incoming exit can keep its own selected entrance.
- CREATE ARRIVAL FOR THIS INCOMING EXIT always prepares a new unique entrance.
- ADD / UPDATE ENTRANCE commits it without deleting older entrances.
- Entrance 1 stays when entrance 2 is added.
- Entrances 1 and 2 stay when entrance 3 is added.
- Selecting an incoming exit that already has a linked entrance selects that entrance for editing.
- Updating an existing entrance changes only that entrance.
- Entrances are deleted only with Delete selected entrance.
