Gemini native adapter silently hangs on exec and persistent sessions

[Amyssjj]

Description

The native Gemini adapter in acpx 0.1.13 silently hangs when attempting both exec (one-shot) and persistent sessions. No error output, no timeout — the process just stalls indefinitely.

Steps to Reproduce

1. acpx --format json --json-strict gemini sessions new --name test
2. echo "hello" | acpx --format json --json-strict gemini prompt --session test --file -
3. Process hangs with no output

Expected

JSON event stream with response or error message.

Actual

No output. Process hangs indefinitely until killed.

Environment

• acpx: 0.1.13
• Node: v25.4.0
• OS: macOS (arm64, Darwin 25.4.0)
• Gemini CLI: installed via google-gemini-cli auth

Notes

Claude adapter works for session creation but fails on prompt (separate issue in zed-industries/claude-agent-acp#357). Codex adapter untested.