opencode run hangs after 'event connected' — no model request ever made (DeepSeek, Linux)

Summary

opencode run hangs indefinitely right after the session is created ("event connected" in the log) and no request is ever made to the model provider. The spinner shows the model (> build · deepseek-chat) but the run never completes, even with a valid API key and working network.

Environment

• OS: Linux ubuntu-docker-compose 6.8.0-138-generic x86_64 (Ubuntu)
• opencode: 1.18.21 (also reproduced with 1.17.12)
• node: v18.19.1 (for the 1.17 postinstall test)
• Provider: deepseek (deepseek-chat), API key via config ~/.config/opencode/opencode.json apiKey and via DEEPSEEK_API_KEY env
• Reproduction environments: (1) a Docker container (restricted, no capabilities) and (2) a bare-metal Ubuntu host — both hang identically

Steps to reproduce

1. Install opencode 1.18.21 (official installer).
2. Configure DeepSeek provider (or use DEEPSEEK_API_KEY env).
3. Run: opencode run 'Respond with exactly: OK'
4. Observe: the command hangs forever; the log stops at message="event connected".

Expected behavior

opencode run completes and prints the assistant response.

Actual behavior

• The process never exits (killed only by timeout).
• Log tail always ends at:

message=created id=ses_... version=1.18.21 ... model=undefined ...
message="event connected"

• With --print-logs: nothing after "event connected" — no HTTP request is attempted.
• Network verified: curl https://api.deepseek.com/v1/models returns 200 from the same host; models.dev and opencode.ai also 200.
• The only successful run was the very first execution right after installation; every subsequent run hangs (even after deleting ~/.local/share/opencode and ~/.cache/opencode).

Notes

• Same behaviour in the official npm binary (1.18.21, bun-compiled) and the 1.17.12 npm package (after running postinstall.mjs to fetch the real binary).
• No crash, no error output — just a silent hang after "event connected".
• This blocks all non-interactive/headless usage (CI, agent orchestration).