✨ [feat] host: detect OpenCode and read a config host key #39

Problem

super-board cannot tell it is running inside OpenCode, and there is nowhere to record which host a project uses, so a shell with no host sign has to ask every time. Part of #30, decisions 2 and 6.

Context

• Where: scripts/super-board-host.sh, tests/test-host.sh, skills/super-board/references/config-schema.json, scripts/super-board-setup.py (check)
  • a. After ✨ [feat] host: unknown host asks for a selection, not Claude #35, the script prints claude or codex from env signs, accepts SUPER_BOARD_HOST=claude|codex|opencode, and exits 65 when it finds no sign.
  • b. The board config has worker_backend (workflow / claude-p) and no host setting.
  • c. OpenCode is believed to export OPENCODE=1 to the shells it runs; confirm on a real OpenCode shell and record the version and variables in the script header, the way the Codex signal is recorded.
• Who: the run orchestrator, onboard, and anyone using super-board from OpenCode.

Fix

Detect OpenCode from its env sign. Add a host config key (claude|codex|opencode), separate from worker_backend. super-board-host.sh --config <file> uses that key when no override and no env sign is present. Order: SUPER_BOARD_HOST, then Codex ids, then the OpenCode sign, then CLAUDECODE, then config host, else exit 65. Setup's check rejects any other host value.

Acceptance Criteria

• tests/test-host.sh: the OpenCode sign alone prints opencode; SUPER_BOARD_HOST=claude with the OpenCode sign prints claude; a Codex id with the OpenCode sign prints codex.
• tests/test-host.sh: an empty env with --config pointing at {"host":"codex"} prints codex; an empty env with no host key still exits 65.
• config-schema.json documents host next to worker_backend, and a tests/test-setup.sh case shows setup's check flags "host": "gemini" and accepts each of the three values.
• bash tests/run-safety.sh passes.

Risk

🟢 Low · additive detection; existing Claude and Codex signals keep their answers.

Blocked by

• ✨ [feat] host: unknown host asks for a selection, not Claude #35 — the exit-65 fallback and the opencode override value this builds on land there.