feat(team): deepseek実装タスク向けidleタイムアウトを延長

[terisuke]

Summary

• Issue feat(team): long-running implementation tasks on deepseek-v4-flash hit the hard 600s idle timeout #286: /team worker の hard wait が 600s 固定で、deepseek-v4-flash の複数ファイル実装が Timed out ... (status busy) で落ちる
• write / deepseek のデフォルトを 20 分 (1200s) に延長。read-only は従来どおり 10 分
• OPENCODE_TEAM_IDLE_TIMEOUT_MS / OPENCODE_TEAM_WRITE_IDLE_TIMEOUT_MS / OPENCODE_TEAM_IDLE_TIMEOUT_MS_<PROVIDER> を文書化
• タイムアウト時に last_tool / last_text と env 再設定ヒントを含める
• 検証スクリプト認識合わせ: AGENTS.md に「inline interpreter は access guard でブロック → in-repo bun test を使う」を追記

Test plan

• bun test test/plugin/team-idle-timeout.test.ts（8 pass）
• 既存 team times out busy child sessions... green
• bun run local:deploy / local:check green
• ライブ: deepseek/write → 1200s、env override → 3000ms
• CI green 後にマージ

Closes #286

Made with Cursor

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