physics: block client-side movement when server roots the player

When SMSG_FORCE_MOVE_ROOT sets ROOT in movementInfo.flags, the
camera controller was not aware and continued to accept directional
input. This caused position desync (client moves, server sees player
as rooted).

- Add movementRooted_ flag to CameraController with setter/getter.
- Block nowForward/nowBackward/nowStrafe when movementRooted_ is set.
- Sync isPlayerRooted() from GameHandler to CameraController each
  frame alongside the existing run-speed sync in application.cpp.
- Add GameHandler::isPlayerRooted() convenience accessor.

include/game/game_handler.hpp

@@ -1152,6 +1152,9 @@ public:
     bool isMounted() const { return currentMountDisplayId_ != 0; }
     bool isHostileAttacker(uint64_t guid) const { return hostileAttackers_.count(guid) > 0; }
     float getServerRunSpeed() const { return serverRunSpeed_; }
+    bool isPlayerRooted() const {
+        return (movementInfo.flags & static_cast<uint32_t>(MovementFlags::ROOT)) != 0;
+    }
     void dismount();
 
     // Taxi / Flight Paths