feat(agents): Phase 7-10 hook system, plugins, skills, orchestration

Phase 7: Built-in Hooks (audit_log, dangerous_confirmation, security_scan)
Phase 8: Plugin system (PluginManager, PluginSandbox, PluginManifest)
Phase 9: Skills registry (SkillRegistry, local/plugin/MCP loaders)
Phase 10: TeamLeader, RemoteTransport, BackgroundTaskManager

backend/app/agents/tools/hooks/builtins/audit_log.py

@@ -0,0 +1,115 @@
+"""审计日志 Hook - Phase 7.2
+
+记录所有工具调用到审计日志。
+"""
+
+from typing import Any
+
+from app.agents.tools.hooks.types import (
+    ExecutionContext,
+    HookResult,
+    HookType,
+)
+from app.agents.tools.manifest import ToolCategory
+
+
+class AuditLogHook:
+    """审计日志 Hook
+
+    记录所有工具调用的详细信息，包括：
+    - 调用时间
+    - 工具名称
+    - 输入参数
+    - 执行结果
+    - 执行时长
+    - 用户 ID
+    """
+
+    def __init__(self, log_path: str | None = None):
+        """
+        Args:
+            log_path: 日志文件路径，None 则输出到 stdout
+        """
+        self.log_path = log_path
+        self._logs: list[dict[str, Any]] = []
+
+    async def pre_tool_use(self, context: ExecutionContext) -> HookResult:
+        """工具执行前记录"""
+        log_entry = {
+            "event": "pre_tool",
+            "tool_name": context.tool_name,
+            "input": context.tool_input,
+            "user_id": context.user_id,
+            "session_id": context.session_id,
+        }
+        self._logs.append(log_entry)
+        self._write_log(log_entry)
+        return HookResult(
+            hook_name="audit_log",
+            success=True,
+            continue_execution=True,
+        )
+
+    async def post_tool_use(self, context: ExecutionContext, result: Any) -> HookResult:
+        """工具执行后记录"""
+        log_entry = {
+            "event": "post_tool",
+            "tool_name": context.tool_name,
+            "result": str(result)[:500] if result else None,
+            "duration_ms": (
+                (context.end_time - context.start_time) * 1000
+                if context.start_time and context.end_time
+                else None
+            ),
+        }
+        self._logs.append(log_entry)
+        self._write_log(log_entry)
+        return HookResult(
+            hook_name="audit_log",
+            success=True,
+            continue_execution=True,
+            modified_output=result,
+        )
+
+    async def tool_error(self, context: ExecutionContext, error: Exception) -> HookResult:
+        """工具出错时记录"""
+        log_entry = {
+            "event": "tool_error",
+            "tool_name": context.tool_name,
+            "error": str(error),
+            "error_type": type(error).__name__,
+        }
+        self._logs.append(log_entry)
+        self._write_log(log_entry)
+        return HookResult(
+            hook_name="audit_log",
+            success=False,
+            continue_execution=True,
+            error=str(error),
+        )
+
+    def _write_log(self, entry: dict[str, Any]) -> None:
+        """写入日志"""
+        import json
+        import datetime
+
+        entry["timestamp"] = datetime.datetime.now().isoformat()
+
+        if self.log_path:
+            try:
+                with open(self.log_path, "a", encoding="utf-8") as f:
+                    f.write(json.dumps(entry, ensure_ascii=False) + "\n")
+            except Exception:
+                # 日志写入失败不影响主流程
+                pass
+        else:
+            # 输出到 stdout
+            print(f"[AUDIT] {json.dumps(entry, ensure_ascii=False)}")
+
+    def get_logs(self) -> list[dict[str, Any]]:
+        """获取所有日志"""
+        return self._logs.copy()
+
+    def clear_logs(self) -> None:
+        """清空日志"""
+        self._logs.clear()