Surface dit-vae/ace-qwen3 binary stderr in server logs

[Copilot]

Binary failures from dit-vae and ace-qwen3 were producing only Generation failed in the server log with no detail. The progress-handler callbacks only matched specific [DiT]/[VAE]/[Phase1]/[Decode] patterns and silently dropped everything else — including all error output from the binary.

Changes

• makeDitVaeProgressHandler / makeLmProgressHandler: add fallback console.log for unrecognized lines so all binary output ([Audio], [Load], [Cover], [Request], errors, etc.) is visible in real-time:

  // Any unrecognized line — log it so binary errors/warnings are always visible
  console.log(`[dit-vae] ${line}`);

• runBinary:

  • Removed the if (onLine) guard around lineBuf — the buffer is now always populated regardless of whether a callback is provided.
  • Flush remaining lineBuf content into onLine on process close — the last line (no trailing \n) was previously lost.
  • On non-zero exit, explicitly log exit code + full stderr/stdout before rejecting, so failures are unmissable even when the binary crashes before producing any progress output:

    console.error(`[${label}] exited with code ${code ?? 'null (terminated by signal)'}`);
    if (stderr) console.error(`[${label}] stderr:\n${stderr}`);

---

🔒 GitHub Advanced Security automatically protects Copilot coding agent pull requests. You can protect all pull requests by enabling Advanced Security for your repositories. Learn more about Advanced Security.