Forward renderer - cleanup, separated static-meshes functionality (#3472)

* var to let & const

* moved static meshes code to separate file

* removed obsolete call

* change to forward renderer constructor, added missing members

* removed the change where forward renderer accepts scene in a constructor

* removed parameter

Co-authored-by: Martin Valigursky <mvaligursky@snapchat.com>

Author: mvaligursky

src/framework/application.js

@@ -1658,10 +1658,6 @@ class Application extends EventHandler {
     }
 
     _firstBatch() {
-        if (this.scene._needsStaticPrepare) {
-            this.renderer.prepareStaticMeshes(this.graphicsDevice, this.scene);
-            this.scene._needsStaticPrepare = false;
-        }
         this.batcher.generate();
     }