Carry each billboard particle's resident texture handle in the instance ABI so stable retail alpha ordering can batch mixed textures without rebinding and redrawing each short texture run. Keep DAT blend transitions as the only billboard draw boundary.
The connected 0xC95B stress scene improved from 6 FPS / 171 ms to about 153 FPS / 6.6 ms at the same roughly 21,000 visible entities. Release build succeeds and all 5,916 tests pass with five intentional skips.
Co-authored-by: OpenAI Codex <codex@openai.com>
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