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/toml.py

@@ -0,0 +1,47 @@
+import json
+from pathlib import Path
+from typing import Iterator, List, Union
+
+from langchain_core.documents import Document
+
+from langchain_community.document_loaders.base import BaseLoader
+
+
+class TomlLoader(BaseLoader):
+    """Load `TOML` files.
+
+    It can load a single source file or several files in a single
+    directory.
+    """
+
+    def __init__(self, source: Union[str, Path]):
+        """Initialize the TomlLoader with a source file or directory."""
+        self.source = Path(source)
+
+    def load(self) -> List[Document]:
+        """Load and return all documents."""
+        return list(self.lazy_load())
+
+    def lazy_load(self) -> Iterator[Document]:
+        """Lazily load the TOML documents from the source file or directory."""
+        import tomli
+
+        if self.source.is_file() and self.source.suffix == ".toml":
+            files = [self.source]
+        elif self.source.is_dir():
+            files = list(self.source.glob("**/*.toml"))
+        else:
+            raise ValueError("Invalid source path or file type")
+
+        for file_path in files:
+            with file_path.open("r", encoding="utf-8") as file:
+                content = file.read()
+                try:
+                    data = tomli.loads(content)
+                    doc = Document(
+                        page_content=json.dumps(data),
+                        metadata={"source": str(file_path)},
+                    )
+                    yield doc
+                except tomli.TOMLDecodeError as e:
+                    print(f"Error parsing TOML file {file_path}: {e}")