Fixed segfault that happend when you'd exit the ingame-state.

src/main.c

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <assert.h>
+#include <stdio.h>
 
 #include "presentation/states/state_ingame.h"
 #include "presentation/states/state_main_menu.h"
@@ -29,18 +30,16 @@ int main() {
             break;
         }
 
-        Presentation_State *state = presentation_state_machine.current;
-
         // Tick.
-        if(state != NULL && state->tick != NULL) {
-            state->tick(state);
+        if(presentation_state_machine.current != NULL && presentation_state_machine.current->tick != NULL) {
+            presentation_state_machine.current->tick(presentation_state_machine.current);
         }
         
         // Render.
         BeginDrawing();
         {
-            if(state != NULL && state->render != NULL) {
-                state->render(state);
+            if(presentation_state_machine.current != NULL && presentation_state_machine.current->render != NULL) {
+                presentation_state_machine.current->render(presentation_state_machine.current);
             }
         }
         EndDrawing();

src/presentation/states/state_ingame.c

@@ -91,7 +91,10 @@ static void state_render(Presentation_State *state) {
     ClearBackground((Color) { 240, 236, 226, 255 });
 
     Simulation_World *sim_world = &g_current_session->simulation_world;
+    assert(sim_world != NULL);
+
     Game_World *world = sim_world->game_world;
+    assert(world != NULL);
     Grid *grid = &world->grid;
 
     uint32_t grid_total_size = grid->width * grid->height;

src/presentation/states/state_main_menu.c

@@ -10,7 +10,7 @@ static void state_enter(Presentation_State *state) {
     Presentation_State_Main_Menu_Context *ctx = (Presentation_State_Main_Menu_Context *)state->context;
     (void)ctx;
 
-    printf("Entered main menu\n");
+    ctx->mode = Main_Menu_Mode_Home;
 }
 
 static void state_tick(Presentation_State *state) {