winit 0.30.13 removed WindowBuilder and deprecated EventLoop::run. Move
window/GPU creation into ApplicationHandler::resumed, expose AppHandler::setup
hook, switch App::run to run_app, and migrate both examples. pollster becomes a
regular dependency (used by app.rs).
- AppHandler::render now receives the current &Frame; its default
implementation renders the whole scene automatically via
app.render_scene(frame.view()) (Option A). Users can simply not
implement render for full auto-rendering.
- Add Renderer::render_scene: batch-renders every scene entity in a
single render pass. Factored per-mesh draw logic into a private
draw_entity helper shared with Renderer::render.
- Add App::render_scene(view) delegating to the Renderer.
- Fill simple.rs with a real quad (mesh/material/entity) without
importing wgpu; the scene now auto-renders via the trait default.