feat(mixin): add TableBaseMixin and UUIDTableBaseMixin for async CRUD operations

- Implemented TableBaseMixin providing generic CRUD methods and automatic timestamp management.
- Introduced UUIDTableBaseMixin for models using UUID as primary keys.
- Added ListResponse for standardized paginated responses.
- Created TimeFilterRequest and PaginationRequest for filtering and pagination parameters.
- Enhanced get_with_count method to return both item list and total count.
- Included validation for time filter parameters in TimeFilterRequest.
- Improved documentation and usage examples throughout the code.

models/node.py

@@ -1,23 +1,98 @@
-
+from enum import StrEnum
 from typing import TYPE_CHECKING
-from sqlmodel import Field, Relationship, text
-from .base import TableBase
+
+from sqlmodel import Field, Relationship, text, Index
+
+from .base import SQLModelBase
+from .mixin import TableBaseMixin
 
 if TYPE_CHECKING:
     from .download import Download
 
-class Node(TableBase, table=True):
+
+class NodeStatus(StrEnum):
+    """节点状态枚举"""
+    ONLINE = "online"
+    """正常"""
+    OFFLINE = "offline"
+    """离线"""
+
+
+class NodeType(StrEnum):
+    """节点类型枚举"""
+    MASTER = "master"
+    """主节点"""
+    SLAVE = "slave"
+    """从节点"""
+
+
+class Aria2ConfigurationBase(SQLModelBase):
+    """Aria2配置基础模型"""
+
+    rpc_url: str | None = Field(default=None, max_length=255)
+    """RPC地址"""
+
+    rpc_secret: str | None = None
+    """RPC密钥"""
+
+    temp_path: str | None = Field(default=None, max_length=255)
+    """临时下载路径"""
+
+    max_concurrent: int = Field(default=5, ge=1, le=50)
+    """最大并发数"""
+
+    timeout: int = Field(default=300, ge=1)
+    """请求超时时间（秒）"""
+
+
+class Aria2Configuration(Aria2ConfigurationBase, TableBaseMixin):
+    """Aria2配置模型（与Node一对一关联）"""
+
+    node_id: int = Field(foreign_key="node.id", unique=True, index=True)
+    """关联的节点ID"""
+
+    # 反向关系
+    node: "Node" = Relationship(back_populates="aria2_config")
+    """关联的节点"""
+
+
+class Node(SQLModelBase, TableBaseMixin):
     """节点模型"""
-    
-    status: int = Field(default=0, sa_column_kwargs={"server_default": "0"}, description="节点状态: 0=正常, 1=离线")
-    name: str = Field(max_length=255, unique=True, description="节点名称")
-    type: int = Field(default=0, sa_column_kwargs={"server_default": "0"}, description="节点类型")
-    server: str = Field(max_length=255, description="节点地址（IP或域名）")
-    slave_key: str | None = Field(default=None, description="从机通讯密钥")
-    master_key: str | None = Field(default=None, description="主机通讯密钥")
-    aria2_enabled: bool = Field(default=False, sa_column_kwargs={"server_default": text("false")}, description="是否启用Aria2")
-    aria2_options: str | None = Field(default=None, description="Aria2配置 (JSON格式)")
-    rank: int = Field(default=0, sa_column_kwargs={"server_default": "0"}, description="节点排序权重")
+
+    __table_args__ = (
+        Index("ix_node_status", "status"),
+    )
+
+    status: NodeStatus = Field(default=NodeStatus.ONLINE, sa_column_kwargs={"server_default": "'online'"})
+    """节点状态"""
+
+    name: str = Field(max_length=255, unique=True)
+    """节点名称"""
+
+    type: NodeType
+    """节点类型"""
+
+    server: str = Field(max_length=255)
+    """节点地址（IP或域名）"""
+
+    slave_key: str | None = Field(default=None, max_length=255)
+    """从机通讯密钥"""
+
+    master_key: str | None = Field(default=None, max_length=255)
+    """主机通讯密钥"""
+
+    aria2_enabled: bool = Field(default=False, sa_column_kwargs={"server_default": text("false")})
+    """是否启用Aria2"""
+
+    rank: int = Field(default=0, sa_column_kwargs={"server_default": "0"})
+    """节点排序权重"""
 
     # 关系
-    downloads: list["Download"] = Relationship(back_populates="node")
+    aria2_config: Aria2Configuration | None = Relationship(
+        back_populates="node",
+        sa_relationship_kwargs={"uselist": False},
+    )
+    """Aria2配置"""
+
+    downloads: list["Download"] = Relationship(back_populates="node")
+    """该节点的下载任务"""