A WiFi notice preempts the current screen within about a second (frame loops, post-loop check, make-up dwell), and an interrupted Vegas iteration that yielded for a notice ends the pass so the notice shows next. Goldens: wifi_notice, vegas. First of three run-loop fixes (#712, #713, #714), pre-tested together.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Adds golden trace tests for DisplayController.run() (test/test_run_loop_golden.py on a fake clock with fake plugins, 15 scenarios, fixtures in test/fixtures/run_loop_golden/) and moves twelve blocks of run() into named helpers (_dispatch_first_frame, _resolve_durations, _resolve_active_mode, _needs_high_fps, _advance_after_screen and others) with the traces identical before and after. docs/RUN_LOOP_REDESIGN.md describes the target structure. Hardware-checked on hdpi: Vegas late-frame rate unchanged in an ABBA A/B.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>