feat(aibox): batch C once mode hardening

- SQLite WAL：subsystems/db.py 建库时 PRAGMA journal_mode=WAL，缓解多 CLI 进程并发写锁
- --worker-only CLI 参数：纯执行面模式（tool_profile=worker），注入精简 system prompt 避免人格/身份提示词污染
- --model / --temperature 覆盖参数：DeepSeekChat 构造透传，create_llm_client 与 stream_chat 两处生效
- 子代理工具失败透传：run_full_subagent(outcome) → SubAgentTool 打 _SUBAGENT_TOOL_FAILED_MARKER → _handle_tool_calls 检测置 orchestrator stats.tool_failed 并剥离标记
- Batch C 单测 5 项：worker profile 工具集、model/temperature 构造、子代理失败标记透传与剥离

aibox/subsystems/db.py

@@ -36,6 +36,8 @@ class MemoryDatabase:
     def _init_database(self):
         """初始化数据库表"""
         with sqlite3.connect(self.db_path) as conn:
+            # WAL 模式：读写并发不互斥，缓解多 CLI 进程并发写锁等待
+            conn.execute("PRAGMA journal_mode=WAL")
             cursor = conn.cursor()
             cursor.execute('''
                 CREATE TABLE IF NOT EXISTS memories (