V266 - V258 base

Fixes the installer failure: "slot-owner-only Character icon gate is missing" when upgrading a live UI that already contains an older Character Record wrapper.

Character Record access law:
- ownerSlot == localSlot: Character icon and portrait right-click may open the normal main Character Record panel.
- ownerSlot != localSlot: Character Record access is denied.
- Portrait left-click isolation from V258 remains unchanged.
- Native BG2 Character Export remains restored.
- No automatic backups are added.
