feat: New world options + Request Gun Van anywhere (#2393)

+ World -> Gravity Editor (with presets for ease of use)
+ World -> Waypoint Beacon
+ World -> Objective Beacon
+ World -> Time And Weather -> Ground Snow
+ Self -> Mobile -> Request Gun Van (spawns the gun van right in front of you no matter where you are)

src/pointers.cpp

@@ -42,6 +42,24 @@ namespace big
                 g_pointers->m_gta.m_ocean_quads = ptr.add(5).rip().as<uint64_t>();
             }
         },
+        // Gravity Level
+        {
+            "GL",
+            "48 8D 0D ? ? ? ? F3 0F 10 04 81 F3 0F 11 05",
+            [](memory::handle ptr)
+            {
+                g_pointers->m_gta.m_gravity_level = ptr.add(3).rip().as<float*>();
+            }
+        },
+        // Set Gravity Level
+        {
+            "SGL",
+            "48 83 EC ? 83 F9 ? 77 ? 48 63 C1 48 8D 0D",
+            [](memory::handle ptr)
+            {
+                g_pointers->m_gta.m_set_gravity_level = ptr.as<functions::set_gravity_level>();
+            }
+        },
         // Game State
         {
             "GS",