Fix command log streaming race#5789
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runAndStreamAux funnels a command's stdout and stderr into a single cmdWriter (the command-log panel, or a buffer when output is suppressed) from two separate goroutines: stderr through the MultiWriter set on cmd.Stderr, and stdout through the onRun callback. Those goroutines wrote the shared writer without any synchronization, racing on the prefixWriter's prefixWritten flag and interleaving the two streams. Wrap the writer so its writes are serialized. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
…uffers runAndStreamAux reads the stdout buffer (and, when output is suppressed, the combinedOutput buffer) for its error message after handler.wait() returns, but the goroutine that fills those buffers by draining the command's output isn't awaited, so the reads raced its final writes. Own the goroutine here rather than letting the onRun callbacks spawn it, and join it before reading the buffers. The pty reader reaches EOF on its own once the process exits, but the non-pty pipe never does, so its handler now closes the read end to unblock the reader; the pipe is synchronous, so by the time the command has exited all of its output has already been read and nothing is lost. This also plugs the goroutine that the non-pty streaming path previously leaked on every command. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Serialize concurrent writes to the streamed command's output writer.
runAndStreamAuxfunnels a command's stdout and stderr into a singlecmdWriter(the command-log panel, or a buffer when output is suppressed) from two separate goroutines: stderr through the MultiWriter set oncmd.Stderr, and stdout through theonRuncallback. Those goroutineswrote the shared writer without any synchronization, racing on the prefixWriter's
prefixWrittenflag and interleaving the two streams. Wrap the writer so its writes are serialized.