feat(agents): Phase 6 tool system refactoring

Phase 6.1: ToolRegistry infrastructure
- Add ToolManifest with ToolCategory, PermissionClass, SideEffectScope
- Add ToolRegistry singleton with register/get/unregister/list/search
- Add BaseTool abstract class with ReadTool/WriteTool/DBWriteTool/ExternalTool/NetworkTool subclasses
- Add migration layer for backward compatibility

Phase 6.2: Hook interception system
- Add HookType (PRE_TOOL_USE, POST_TOOL_USE, TOOL_ERROR, TOOL_SKIP)
- Add HookManager with singleton for hook registration
- Add HookExecutor for pre/post/error hook execution

Phase 6.3: Streaming execution
- Add StreamingToolExecutor with batch execution support

Phase 6.4: New builtin tools
- Add file_tools: GlobTool, GrepTool, ReadFileTool, WriteFileTool
- Add system_tools: BashTool, PowerShellTool
- Add dev_tools: LSPTools, GitTool
- Add collaboration_tools: TeamAgentTool, TaskBroadcastTool

Tests: 29 passed

backend/app/agents/tools/manifest.py

@@ -0,0 +1,77 @@
+"""工具元数据和数据类型定义"""
+
+from dataclasses import dataclass, field
+from enum import Enum
+from typing import Any
+
+
+class ToolCategory(Enum):
+    """工具类别"""
+
+    READ = "read"
+    WRITE = "write"
+    EXTERNAL = "external"
+    DB_WRITE = "db_write"
+    NETWORK = "network"
+
+
+class SideEffectScope(Enum):
+    """副作用范围"""
+
+    NONE = "none"
+    LOCAL_STATE = "local_state"
+    DB_WRITE = "db_write"
+    NETWORK = "network"
+
+
+class PermissionClass(Enum):
+    """权限级别"""
+
+    READ = "read"
+    WRITE = "write"
+    EXTERNAL = "external"
+
+
+@dataclass
+class ToolManifest:
+    """工具元数据"""
+
+    name: str
+    description: str
+    category: ToolCategory
+    parameters: dict[str, Any]  # JSON Schema
+    return_schema: dict[str, Any]
+    permission_class: PermissionClass
+    side_effect_scope: SideEffectScope
+    requires_confirmation: bool = False
+    is_streaming: bool = False
+    tags: list[str] = field(default_factory=list)
+
+    def to_dict(self) -> dict[str, Any]:
+        return {
+            "name": self.name,
+            "description": self.description,
+            "category": self.category.value,
+            "parameters": self.parameters,
+            "return_schema": self.return_schema,
+            "permission_class": self.permission_class.value,
+            "side_effect_scope": self.side_effect_scope.value,
+            "requires_confirmation": self.requires_confirmation,
+            "is_streaming": self.is_streaming,
+            "tags": self.tags,
+        }
+
+
+@dataclass
+class HookConfig:
+    """Hook 配置"""
+
+    name: str
+    hook_type: str  # "pre_tool_use", "post_tool_use", "tool_error", "tool_skip"
+    filter_names: list[str] | None = None  # 只对特定工具生效，None 表示全部
+
+    def matches_tool(self, tool_name: str) -> bool:
+        """检查 Hook 是否对指定工具生效"""
+        if self.filter_names is None:
+            return True
+        return tool_name in self.filter_names