chore: 添加虚拟环境到仓库

- 添加 backend_service/venv 虚拟环境
- 包含所有Python依赖包
- 注意：虚拟环境约393MB，包含12655个文件

backend_service/venv/lib/python3.13/site-packages/chromadb/segment/distributed/__init__.py

@@ -0,0 +1,80 @@
+from abc import abstractmethod
+from dataclasses import dataclass
+from typing import Any, Callable, List
+
+from overrides import EnforceOverrides, overrides
+from chromadb.config import Component, System
+from chromadb.types import Segment
+
+
+class SegmentDirectory(Component):
+    """A segment directory is a data interface that manages the location of segments. Concretely, this
+    means that for distributed chroma, it provides the grpc endpoint for a segment."""
+
+    @abstractmethod
+    def get_segment_endpoints(self, segment: Segment, n: int) -> List[str]:
+        """Return the segment residences for a given segment ID. Will return at most n residences.
+        Should only return less than n residences if there are less than n residences available.
+        """
+
+    @abstractmethod
+    def register_updated_segment_callback(
+        self, callback: Callable[[Segment], None]
+    ) -> None:
+        """Register a callback that will be called when a segment is updated"""
+        pass
+
+
+@dataclass
+class Member:
+    id: str
+    ip: str
+    node: str
+
+
+Memberlist = List[Member]
+
+
+class MemberlistProvider(Component, EnforceOverrides):
+    """Returns the latest memberlist and provdes a callback for when it changes. This
+    callback may be called from a different thread than the one that called. Callers should ensure
+    that they are thread-safe."""
+
+    callbacks: List[Callable[[Memberlist], Any]]
+
+    def __init__(self, system: System):
+        self.callbacks = []
+        super().__init__(system)
+
+    @abstractmethod
+    def get_memberlist(self) -> Memberlist:
+        """Returns the latest memberlist"""
+        pass
+
+    @abstractmethod
+    def set_memberlist_name(self, memberlist: str) -> None:
+        """Sets the memberlist that this provider will watch"""
+        pass
+
+    @overrides
+    def stop(self) -> None:
+        """Stops watching the memberlist"""
+        self.callbacks = []
+
+    def register_updated_memberlist_callback(
+        self, callback: Callable[[Memberlist], Any]
+    ) -> None:
+        """Registers a callback that will be called when the memberlist changes. May be called many times
+        with the same memberlist, so callers should be idempotent. May be called from a different thread.
+        """
+        self.callbacks.append(callback)
+
+    def unregister_updated_memberlist_callback(
+        self, callback: Callable[[Memberlist], Any]
+    ) -> bool:
+        """Unregisters a callback that was previously registered. Returns True if the callback was
+        successfully unregistered, False if it was not ever registered."""
+        if callback in self.callbacks:
+            self.callbacks.remove(callback)
+            return True
+        return False