render::draw_labels draws a scene's labels over finished pixels in the CPU
rasterizer's font. capture::shared opens the process's device once by the
FIELDCRAFT_GPU policy; capture::png draws on it or on the CPU and reports
which (Renderer).
Refs #422
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo