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/agent_toolkits/sql/base.py

@@ -0,0 +1,108 @@
+"""SQL agent."""
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Any, Dict, List, Optional, Sequence
+
+from langchain_core.callbacks import BaseCallbackManager
+from langchain_core.language_models import BaseLanguageModel
+from langchain_core.messages import AIMessage, SystemMessage
+from langchain_core.prompts.chat import (
+    ChatPromptTemplate,
+    HumanMessagePromptTemplate,
+    MessagesPlaceholder,
+)
+
+from langchain_community.agent_toolkits.sql.prompt import (
+    SQL_FUNCTIONS_SUFFIX,
+    SQL_PREFIX,
+    SQL_SUFFIX,
+)
+from langchain_community.agent_toolkits.sql.toolkit import SQLDatabaseToolkit
+from langchain_community.tools import BaseTool
+
+if TYPE_CHECKING:
+    from langchain.agents.agent import AgentExecutor
+    from langchain.agents.agent_types import AgentType
+
+
+def create_sql_agent(
+    llm: BaseLanguageModel,
+    toolkit: SQLDatabaseToolkit,
+    agent_type: Optional[AgentType] = None,
+    callback_manager: Optional[BaseCallbackManager] = None,
+    prefix: str = SQL_PREFIX,
+    suffix: Optional[str] = None,
+    format_instructions: Optional[str] = None,
+    input_variables: Optional[List[str]] = None,
+    top_k: int = 10,
+    max_iterations: Optional[int] = 15,
+    max_execution_time: Optional[float] = None,
+    early_stopping_method: str = "force",
+    verbose: bool = False,
+    agent_executor_kwargs: Optional[Dict[str, Any]] = None,
+    extra_tools: Sequence[BaseTool] = (),
+    **kwargs: Any,
+) -> AgentExecutor:
+    """Construct an SQL agent from an LLM and tools."""
+    from langchain.agents.agent import AgentExecutor, BaseSingleActionAgent
+    from langchain.agents.agent_types import AgentType
+    from langchain.agents.mrkl.base import ZeroShotAgent
+    from langchain.agents.openai_functions_agent.base import OpenAIFunctionsAgent
+    from langchain.chains.llm import LLMChain
+
+    agent_type = agent_type or AgentType.ZERO_SHOT_REACT_DESCRIPTION
+    tools = toolkit.get_tools() + list(extra_tools)
+    prefix = prefix.format(dialect=toolkit.dialect, top_k=top_k)
+    agent: BaseSingleActionAgent
+
+    if agent_type == AgentType.ZERO_SHOT_REACT_DESCRIPTION:
+        prompt_params = (
+            {"format_instructions": format_instructions}
+            if format_instructions is not None
+            else {}
+        )
+        prompt = ZeroShotAgent.create_prompt(
+            tools,
+            prefix=prefix,
+            suffix=suffix or SQL_SUFFIX,
+            input_variables=input_variables,
+            **prompt_params,
+        )
+        llm_chain = LLMChain(
+            llm=llm,
+            prompt=prompt,
+            callback_manager=callback_manager,
+        )
+        tool_names = [tool.name for tool in tools]
+        agent = ZeroShotAgent(llm_chain=llm_chain, allowed_tools=tool_names, **kwargs)
+
+    elif agent_type == AgentType.OPENAI_FUNCTIONS:
+        messages = [
+            SystemMessage(content=prefix),
+            HumanMessagePromptTemplate.from_template("{input}"),
+            AIMessage(content=suffix or SQL_FUNCTIONS_SUFFIX),
+            MessagesPlaceholder(variable_name="agent_scratchpad"),
+        ]
+        input_variables = ["input", "agent_scratchpad"]
+        _prompt = ChatPromptTemplate(input_variables=input_variables, messages=messages)
+
+        agent = OpenAIFunctionsAgent(
+            llm=llm,
+            prompt=_prompt,
+            tools=tools,
+            callback_manager=callback_manager,
+            **kwargs,
+        )
+    else:
+        raise ValueError(f"Agent type {agent_type} not supported at the moment.")
+
+    return AgentExecutor.from_agent_and_tools(
+        agent=agent,
+        tools=tools,
+        callback_manager=callback_manager,
+        verbose=verbose,
+        max_iterations=max_iterations,
+        max_execution_time=max_execution_time,
+        early_stopping_method=early_stopping_method,
+        **(agent_executor_kwargs or {}),
+    )