zcode-app-cli 3.11.2-19 TUI hangs on startup inside Orca terminal PTY (3.10.2-18 works)

Bug: zcode-app-cli 3.11.2-19 TUI hangs (never draws) when launched inside Orca terminal PTY; 3.10.2-18 works

Environment

• zcode-app-cli 3.11.2-19 (npm), zcode-runtime 0.16.5
• macOS 26 arm64 (Mac Studio)
• Host terminal: Orca 1.4.197 terminal PTY (xterm.js-based)

Symptom

zcode --mode yolo launched inside an Orca terminal:

• 3.10.2-18: TUI draws and works normally (our production worker setup)
• 3.11.2-19: launcher process stays alive (confirmed via ps) but the TUI never draws — no banner, no input box, nothing in ~/.zcode/cli/tui-runtime.log. It hangs silently, indefinitely (observed 25+ min).

The same 3.11.2-19 binary works fine under a plain PTY (script -q log zcode --mode yolo draws the full banner and input box within seconds), and --prompt headless mode works fine (model round-trip OK).

So: TUI-only, PTY-environment-specific, hangs rather than crashes.

Suspected cause

The 3.10.2-19/3.11.2-19 TUI changes (Ctrl+C draft handling, "terminal stream failure safe handling", O(1) thinking-stream tail, transient scrollbars). Possibly a new terminal capability query (e.g. the ESC[?996n sync-output / feature probes visible in our PTY logs) that blocks when the host emulator answers differently than expected.

Repro

1. In Orca (macOS) open any terminal
2. npm i -g zcode-app-cli@3.11.2-19
3. zcode --mode yolo → nothing renders
4. Roll back npm i -g zcode-app-cli@3.10.2-18 → TUI renders immediately

Impact

We run zcode as an unattended worker inside Orca on 3 machines; 3.11.x's "silent stream EOF becomes retryable" fix is directly valuable to us, but we cannot upgrade while the TUI won't start under Orca. Happy to test patches or collect debug output (--verbose/env flag?) if you point us at one.

Reproduce the hang with zcode --mode yolo in Orca using 3.11.2-19, then compare it with 3.10.2-18 and a plain PTY. Check ~/.zcode/cli/tui-runtime.log and the terminal PTY logs, including the ESC[?996n probes; done means the TUI draws and accepts input under Orca without regressing headless --prompt mode.