gpui: Fix native object accumulation in headless Metal rendering (#64099)
# Objective
Heavy headless rendering benchmarks accumulated native temporary objects
across frames because they could run for a long time without an
autorelease pool draining.
This PR adds a scoped autorelease pool around each headless rendering
call so those temporary objects are released promptly. GPU submission
remains asynchronous, and image readback retains its existing completion
wait.
Release Notes:
- N/A
fb38178d74Anthony Eid committed on 9/11/2026, 9:09:33 PM· committed by GitHubparenta936ce0