ecs: fix tests

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

libs/ecs/src/main.zig

@@ -75,8 +75,8 @@ test "example" {
     // Initialize module state.
     var physics = world.mod(.physics);
     var renderer = world.mod(.renderer);
-    physics.setState(.pointer, 123);
-    _ = physics.getState(.pointer); // == 123
+    physics.initState(.{ .pointer = 123 });
+    _ = physics.state().pointer; // == 123
 
     const player1 = try world.newEntity();
     const player2 = try world.newEntity();