The live run-view streamer returns a single snapshot of whatever act_runner
had buffered by poll time. For a job that's still running that's fine (no
persisted log exists yet), but for a job that already finished it silently
truncates wherever the snapshot happened to stop -- the original bug: a
failed nix flake check run returned only the ~90s eval-phase prefix and
dropped the actual build-phase error entirely.
Flip the priority: try the durable persisted-log download first (complete
once it exists), fall back to the streamer only when nothing's persisted
yet (run still live). --step still goes straight to the streamer since the
persisted log is flat and doesn't honor per-step framing.
6339a2384b