community[major], core[patch], langchain[patch], experimental[patch]: Create langchain-community (#14463)

Moved the following modules to new package langchain-community in a backwards compatible fashion:

```
mv langchain/langchain/adapters community/langchain_community
mv langchain/langchain/callbacks community/langchain_community/callbacks
mv langchain/langchain/chat_loaders community/langchain_community
mv langchain/langchain/chat_models community/langchain_community
mv langchain/langchain/document_loaders community/langchain_community
mv langchain/langchain/docstore community/langchain_community
mv langchain/langchain/document_transformers community/langchain_community
mv langchain/langchain/embeddings community/langchain_community
mv langchain/langchain/graphs community/langchain_community
mv langchain/langchain/llms community/langchain_community
mv langchain/langchain/memory/chat_message_histories community/langchain_community
mv langchain/langchain/retrievers community/langchain_community
mv langchain/langchain/storage community/langchain_community
mv langchain/langchain/tools community/langchain_community
mv langchain/langchain/utilities community/langchain_community
mv langchain/langchain/vectorstores community/langchain_community
mv langchain/langchain/agents/agent_toolkits community/langchain_community
mv langchain/langchain/cache.py community/langchain_community
mv langchain/langchain/adapters community/langchain_community
mv langchain/langchain/callbacks community/langchain_community/callbacks
mv langchain/langchain/chat_loaders community/langchain_community
mv langchain/langchain/chat_models community/langchain_community
mv langchain/langchain/document_loaders community/langchain_community
mv langchain/langchain/docstore community/langchain_community
mv langchain/langchain/document_transformers community/langchain_community
mv langchain/langchain/embeddings community/langchain_community
mv langchain/langchain/graphs community/langchain_community
mv langchain/langchain/llms community/langchain_community
mv langchain/langchain/memory/chat_message_histories community/langchain_community
mv langchain/langchain/retrievers community/langchain_community
mv langchain/langchain/storage community/langchain_community
mv langchain/langchain/tools community/langchain_community
mv langchain/langchain/utilities community/langchain_community
mv langchain/langchain/vectorstores community/langchain_community
mv langchain/langchain/agents/agent_toolkits community/langchain_community
mv langchain/langchain/cache.py community/langchain_community
```

Moved the following to core
```
mv langchain/langchain/utils/json_schema.py core/langchain_core/utils
mv langchain/langchain/utils/html.py core/langchain_core/utils
mv langchain/langchain/utils/strings.py core/langchain_core/utils
cat langchain/langchain/utils/env.py >> core/langchain_core/utils/env.py
rm langchain/langchain/utils/env.py
```

See .scripts/community_split/script_integrations.sh for all changes

libs/community/langchain_community/tools/reddit_search/tool.py

@@ -0,0 +1,64 @@
+"""Tool for the Reddit search API."""
+
+from typing import Optional, Type
+
+from langchain_core.callbacks import CallbackManagerForToolRun
+from langchain_core.pydantic_v1 import BaseModel, Field
+from langchain_core.tools import BaseTool
+
+from langchain_community.utilities.reddit_search import RedditSearchAPIWrapper
+
+
+class RedditSearchSchema(BaseModel):
+    """Input for Reddit search."""
+
+    query: str = Field(
+        description="should be query string that post title should \
+        contain, or '*' if anything is allowed."
+    )
+    sort: str = Field(
+        description='should be sort method, which is one of: "relevance" \
+        , "hot", "top", "new", or "comments".'
+    )
+    time_filter: str = Field(
+        description='should be time period to filter by, which is \
+        one of "all", "day", "hour", "month", "week", or "year"'
+    )
+    subreddit: str = Field(
+        description='should be name of subreddit, like "all" for \
+        r/all'
+    )
+    limit: str = Field(
+        description="a positive integer indicating the maximum number \
+        of results to return"
+    )
+
+
+class RedditSearchRun(BaseTool):
+    """Tool that queries for posts on a subreddit."""
+
+    name: str = "reddit_search"
+    description: str = (
+        "A tool that searches for posts on Reddit."
+        "Useful when you need to know post information on a subreddit."
+    )
+    api_wrapper: RedditSearchAPIWrapper = Field(default_factory=RedditSearchAPIWrapper)
+    args_schema: Type[BaseModel] = RedditSearchSchema
+
+    def _run(
+        self,
+        query: str,
+        sort: str,
+        time_filter: str,
+        subreddit: str,
+        limit: str,
+        run_manager: Optional[CallbackManagerForToolRun] = None,
+    ) -> str:
+        """Use the tool."""
+        return self.api_wrapper.run(
+            query=query,
+            sort=sort,
+            time_filter=time_filter,
+            subreddit=subreddit,
+            limit=int(limit),
+        )