fix Anna cheese in 747

[Die4Ever]

we could spawn a doberman about 3 seconds before Anna to clear out any placed LAMs before Anna comes in, as a replacement for the hacky allied LAM

https://discord.com/channels/823629359931195394/823629734457114654/1293423843662364765

when the dog dies, Anna can go aggro

problem with the doberman is it might be too short to trigger LAMs placed up high?

[Die4Ever]

doberman's mass is 25, grenades only get triggered by mass>=40, so it's gonna need to be a big doggo, but that should be fine

40/25 == 1.6

do we use cube root or square root?

cube root of 1.6 means a DrawScale of 1.17, square root means 1.26

and I did test the doberman is tall enough to trigger a LAM on the ceiling, even at default DrawScale/CollisionHeight (with increased mass of course)

[Die4Ever]

I think we set the flags for MS_Anna747Unhidden and MS_AnnaUnhidden just so the mission script doesn't unhide her and we can handle it ourselves, maybe just with a dispatcher