community: use NeuralDB object to initialize NeuralDBVectorStore (#17272)

**Description:** This PR adds an `__init__` method to the
NeuralDBVectorStore class, which takes in a NeuralDB object to
instantiate the state of NeuralDBVectorStore.
**Issue:** N/A
**Dependencies:** N/A
**Twitter handle:** N/A

libs/community/langchain_community/vectorstores/thirdai_neuraldb.py

@@ -12,7 +12,22 @@ from langchain_core.vectorstores import VectorStore
 
 
 class NeuralDBVectorStore(VectorStore):
-    """Vectorstore that uses ThirdAI's NeuralDB."""
+    """Vectorstore that uses ThirdAI's NeuralDB.
+
+    To use, you should have the ``thirdai[neural_db]`` python package installed.
+
+    Example:
+        .. code-block:: python
+
+            from langchain_community.vectorstores import NeuralDBVectorStore
+            from thirdai import neural_db as ndb
+
+            db = ndb.NeuralDB()
+            vectorstore = NeuralDBVectorStore(db=db)
+    """
+
+    def __init__(self, db):
+        self.db = db
 
     db: Any = None  #: :meta private:
     """NeuralDB instance"""
@@ -322,7 +337,6 @@ class NeuralDBVectorStore(VectorStore):
                     metadata={
                         "id": ref.id,
                         "upvote_ids": ref.upvote_ids,
-                        "text": ref.text,
                         "source": ref.source,
                         "metadata": ref.metadata,
                         "score": ref.score,