Join wait: animate through EVERY pre-mission state

Two follow-ups to the waiting-screen work, both user-reported:

1. "Animation frozen after connecting": once the console seats the player
   and sends the egg, the state advances LoadingMission -> WaitingForLaunch
   -- where NOTHING presents until the operator's RunMission, so the last
   idle frame froze on screen with the mission audio already running.
   ExecuteForeground now keeps the idle clear + overlay alive through
   LoadingMission/WaitingForLaunch/LaunchingMission (no early return -- the
   load/replication work continues), and ExecuteIdle picks per-state text:
     WaitingForEgg    "WAITING FOR MISSION ASSIGNMENT"
     Loading/Launching "LOADING MISSION / stand by"
     WaitingForLaunch "MISSION READY / waiting for the operator to launch"

2. The roster-full retry pause was a raw Sleep(3000) -- with the relay up
   and answering SEAT_FULL instantly, the process spent ~95% of its time
   unpumped (IsHungAppWindow TRUE, spinner frozen).  Now 30 pumped 100ms
   slices with the reason on screen ("session is FULL -- waiting for a
   seat to free up").

Verified live against the running operator relay: roster-full wait shows
the reason text, spinner advances across 500ms captures, IsHungAppWindow
false on every sample.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

engine/MUNGA_L4/L4NET.CPP

@@ -1650,7 +1650,18 @@ Logical L4NetworkManager::RelayRequestSeat()
 			full_shown = 1;
 			banner_shown = 1;			// suppress the banner after this
 		}
-		Sleep(3000);
+		{
+			// pumped retry pause (the raw Sleep(3000) froze the window +
+			// spinner whenever the relay answered -- e.g. ROSTER FULL)
+			const char *why = roster_full
+				? "session is FULL -- waiting for a seat to free up"
+				: "retrying...";
+			for (int slice = 0; slice < 30; ++slice)	// 3s
+			{
+				RelayWaitTick("WAITING FOR THE OPERATOR'S SESSION", why);
+				Sleep(100);
+			}
+		}
 	}
 	return False;
 }