Window::Render() rebuilt cmdBufInfo, the subresource range, both
VkImageMemoryBarrier structs, and presentInfo on the stack every frame
even though only the barriers' image (and the acquire barrier's
oldLayout) ever change. Hoist them to members initialised once in the
constructor; Render() now patches only the two varying fields.
presentInfo.pImageIndices/pSwapchains point at the currentBuffer and
swapChain members, so they track value changes (including swapchain
recreation) automatically. The render-complete wait semaphore is fixed
for the window's lifetime, so the per-frame `renderComplete != NULL`
check — set once, never cleared — was dead and is removed; the
semaphore is wired into presentInfo in the constructor instead.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
