STOCK CAMPAIGN SERVER-ONLY UI

This UI.MENU keeps BG2EE's normal campaign interface and resources.
No Baldur's Legend / custom Legacy campaign menu is injected.

One-shot launcher flags:
  Drakhysys / Legacy Server Only = 1
  Drakhysys / Legacy Campaign = 1 (Shadows of Amn), 2 (Throne of Bhaal), 3 (The Black Pits II)

On launch the selected STOCK campaign is activated and BG2 opens Create Multiplayer Game directly.
Join Game, Direct Connect and refresh are disabled while server-only mode is active, so the user remains on the game they create.
Character storage is handled by the account launcher junction. No automatic character backup/copy is added.
