chore(langchain_v1): clean anything uncertain (#32228)

Further clean up of namespace:

- Removed prompts (we'll re-add in a separate commit)
- Remove LocalFileStore until we can review whether all the
implementation details are necessary
- Remove message processing logic from memory (we'll figure out where to
expose it)
- Remove `Tool` primitive (should be sufficient to use `BaseTool` for
typing purposes)
- Remove utilities to create kv stores. Unclear if they've had much
usage outside MultiparentRetriever

Author: eyurtsev

.github/workflows/pr_lint.yml

@@ -81,6 +81,7 @@ jobs:
             core
             cli
             langchain
+            langchain_v1
             standard-tests
             text-splitters
             docs

libs/langchain_v1/.dockerignore

@@ -1,24 +1,5 @@
-"""**Chat Models** are a variation on language models.
-
-While Chat Models use language models under the hood, the interface they expose
-is a bit different. Rather than expose a "text in, text out" API, they expose
-an interface where "chat messages" are the inputs and outputs.
-
-**Class hierarchy:**
-
-.. code-block::
-
-    BaseLanguageModel --> BaseChatModel --> <name>  # Examples: ChatOpenAI, ChatGooglePalm
-
-**Main helpers:**
-
-.. code-block::
-
-    AIMessage, BaseMessage, HumanMessage
-"""  # noqa: E501
+from langchain_core.language_models import BaseChatModel
 
 from langchain.chat_models.base import init_chat_model
 
-__all__ = [
-    "init_chat_model",
-]
+__all__ = ["BaseChatModel", "init_chat_model"]

libs/langchain_v1/langchain/chat_models/__init__.py

@@ -1,7 +1,10 @@
+from langchain_core.embeddings import Embeddings
+
 from langchain.embeddings.base import init_embeddings
 from langchain.embeddings.cache import CacheBackedEmbeddings
 
 __all__ = [
     "CacheBackedEmbeddings",
+    "Embeddings",
     "init_embeddings",
 ]

libs/langchain_v1/langchain/embeddings/__init__.py

@@ -12,16 +12,11 @@
     InvalidKeyException,
 )
 
-from langchain.storage._lc_store import create_kv_docstore, create_lc_store
 from langchain.storage.encoder_backed import EncoderBackedStore
-from langchain.storage.file_system import LocalFileStore
 
 __all__ = [
     "EncoderBackedStore",
     "InMemoryByteStore",
     "InMemoryStore",
     "InvalidKeyException",
-    "LocalFileStore",
-    "create_kv_docstore",
-    "create_lc_store",
 ]