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/document_loaders/chatgpt.py

@@ -0,0 +1,65 @@
+import datetime
+import json
+from typing import List
+
+from langchain_core.documents import Document
+
+from langchain_community.document_loaders.base import BaseLoader
+
+
+def concatenate_rows(message: dict, title: str) -> str:
+    """
+    Combine message information in a readable format ready to be used.
+    Args:
+        message: Message to be concatenated
+        title: Title of the conversation
+
+    Returns:
+        Concatenated message
+    """
+    if not message:
+        return ""
+
+    sender = message["author"]["role"] if message["author"] else "unknown"
+    text = message["content"]["parts"][0]
+    date = datetime.datetime.fromtimestamp(message["create_time"]).strftime(
+        "%Y-%m-%d %H:%M:%S"
+    )
+    return f"{title} - {sender} on {date}: {text}\n\n"
+
+
+class ChatGPTLoader(BaseLoader):
+    """Load conversations from exported `ChatGPT` data."""
+
+    def __init__(self, log_file: str, num_logs: int = -1):
+        """Initialize a class object.
+
+        Args:
+            log_file: Path to the log file
+            num_logs: Number of logs to load. If 0, load all logs.
+        """
+        self.log_file = log_file
+        self.num_logs = num_logs
+
+    def load(self) -> List[Document]:
+        with open(self.log_file, encoding="utf8") as f:
+            data = json.load(f)[: self.num_logs] if self.num_logs else json.load(f)
+
+        documents = []
+        for d in data:
+            title = d["title"]
+            messages = d["mapping"]
+            text = "".join(
+                [
+                    concatenate_rows(messages[key]["message"], title)
+                    for idx, key in enumerate(messages)
+                    if not (
+                        idx == 0
+                        and messages[key]["message"]["author"]["role"] == "system"
+                    )
+                ]
+            )
+            metadata = {"source": str(self.log_file)}
+            documents.append(Document(page_content=text, metadata=metadata))
+
+        return documents