Refactor message sending architecture and implement legacy driver support

- Removed UniversalMessageSender from group_generator.py and private_generator.py.
- Updated PlatformIOManager to manage legacy send drivers and ensure send pipeline readiness.
- Enhanced LegacyPlatformDriver to utilize prepared messages for sending.
- Refactored send_service to unify message sending logic and integrate with Platform IO.
- Added regression tests for Platform IO legacy driver and send service functionality.

src/platform_io/drivers/legacy_driver.py

@@ -1,16 +1,16 @@
-"""提供 Platform IO 的 legacy 传输驱动骨架。"""
+"""提供 Platform IO 的 legacy 传输驱动实现。"""
 
 from typing import TYPE_CHECKING, Any, Dict, Optional
 
 from src.platform_io.drivers.base import PlatformIODriver
-from src.platform_io.types import DeliveryReceipt, DriverDescriptor, DriverKind, RouteKey
+from src.platform_io.types import DeliveryReceipt, DeliveryStatus, DriverDescriptor, DriverKind, RouteKey
 
 if TYPE_CHECKING:
     from src.chat.message_receive.message import SessionMessage
 
 
 class LegacyPlatformDriver(PlatformIODriver):
-    """面向 ``maim_message`` 旧链路的 Platform IO 驱动骨架。"""
+    """面向 ``UniversalMessageSender`` 旧链的 Platform IO 驱动。"""
 
     def __init__(
         self,
@@ -25,7 +25,7 @@ class LegacyPlatformDriver(PlatformIODriver):
         Args:
             driver_id: Broker 内的唯一驱动 ID。
             platform: 该 legacy 适配器链路负责的平台。
-            account_id: 可选的账号 ID 或 self ID。
+            account_id: 可选的账号 ID。
             scope: 可选的额外路由作用域。
             metadata: 可选的额外驱动元数据。
         """
@@ -45,7 +45,7 @@ class LegacyPlatformDriver(PlatformIODriver):
         route_key: RouteKey,
         metadata: Optional[Dict[str, Any]] = None,
     ) -> DeliveryReceipt:
-        """通过 legacy 传输路径发送消息。
+        """通过旧链发送一条已经过预处理的消息。
 
         Args:
             message: 要投递的内部会话消息。
@@ -53,9 +53,40 @@ class LegacyPlatformDriver(PlatformIODriver):
             metadata: 本次出站投递可选的 Broker 侧元数据。
 
         Returns:
-            DeliveryReceipt: 由驱动返回的规范化回执。
-
-        Raises:
-            NotImplementedError: 当前仍处于骨架阶段，尚未真正接入旧发送链。
+            DeliveryReceipt: 规范化后的发送回执。
         """
-        raise NotImplementedError("LegacyPlatformDriver 仅完成地基实现，尚未接入旧发送链")
+        from src.chat.message_receive.uni_message_sender import send_prepared_message_to_platform
+
+        show_log = False
+        if isinstance(metadata, dict):
+            show_log = bool(metadata.get("show_log", False))
+
+        try:
+            sent = await send_prepared_message_to_platform(message, show_log=show_log)
+        except Exception as exc:
+            return DeliveryReceipt(
+                internal_message_id=message.message_id,
+                route_key=route_key,
+                status=DeliveryStatus.FAILED,
+                driver_id=self.driver_id,
+                driver_kind=self.descriptor.kind,
+                error=str(exc),
+            )
+
+        if not sent:
+            return DeliveryReceipt(
+                internal_message_id=message.message_id,
+                route_key=route_key,
+                status=DeliveryStatus.FAILED,
+                driver_id=self.driver_id,
+                driver_kind=self.descriptor.kind,
+                error="旧链发送失败",
+            )
+
+        return DeliveryReceipt(
+            internal_message_id=message.message_id,
+            route_key=route_key,
+            status=DeliveryStatus.SENT,
+            driver_id=self.driver_id,
+            driver_kind=self.descriptor.kind,
+        )