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/assemblyai.py

@@ -0,0 +1,112 @@
+from __future__ import annotations
+
+from enum import Enum
+from typing import TYPE_CHECKING, List, Optional
+
+from langchain_core.documents import Document
+
+from langchain_community.document_loaders.base import BaseLoader
+
+if TYPE_CHECKING:
+    import assemblyai
+
+
+class TranscriptFormat(Enum):
+    """Transcript format to use for the document loader."""
+
+    TEXT = "text"
+    """One document with the transcription text"""
+    SENTENCES = "sentences"
+    """Multiple documents, splits the transcription by each sentence"""
+    PARAGRAPHS = "paragraphs"
+    """Multiple documents, splits the transcription by each paragraph"""
+    SUBTITLES_SRT = "subtitles_srt"
+    """One document with the transcript exported in SRT subtitles format"""
+    SUBTITLES_VTT = "subtitles_vtt"
+    """One document with the transcript exported in VTT subtitles format"""
+
+
+class AssemblyAIAudioTranscriptLoader(BaseLoader):
+    """
+    Loader for AssemblyAI audio transcripts.
+
+    It uses the AssemblyAI API to transcribe audio files
+    and loads the transcribed text into one or more Documents,
+    depending on the specified format.
+
+    To use, you should have the ``assemblyai`` python package installed, and the
+    environment variable ``ASSEMBLYAI_API_KEY`` set with your API key.
+    Alternatively, the API key can also be passed as an argument.
+
+    Audio files can be specified via an URL or a local file path.
+    """
+
+    def __init__(
+        self,
+        file_path: str,
+        *,
+        transcript_format: TranscriptFormat = TranscriptFormat.TEXT,
+        config: Optional[assemblyai.TranscriptionConfig] = None,
+        api_key: Optional[str] = None,
+    ):
+        """
+        Initializes the AssemblyAI AudioTranscriptLoader.
+
+        Args:
+            file_path: An URL or a local file path.
+            transcript_format: Transcript format to use.
+                See class ``TranscriptFormat`` for more info.
+            config: Transcription options and features. If ``None`` is given,
+                the Transcriber's default configuration will be used.
+            api_key: AssemblyAI API key.
+        """
+        try:
+            import assemblyai
+        except ImportError:
+            raise ImportError(
+                "Could not import assemblyai python package. "
+                "Please install it with `pip install assemblyai`."
+            )
+        if api_key is not None:
+            assemblyai.settings.api_key = api_key
+
+        self.file_path = file_path
+        self.transcript_format = transcript_format
+        self.transcriber = assemblyai.Transcriber(config=config)
+
+    def load(self) -> List[Document]:
+        """Transcribes the audio file and loads the transcript into documents.
+
+        It uses the AssemblyAI API to transcribe the audio file and blocks until
+        the transcription is finished.
+        """
+        transcript = self.transcriber.transcribe(self.file_path)
+        # This will raise a ValueError if no API key is set.
+
+        if transcript.error:
+            raise ValueError(f"Could not transcribe file: {transcript.error}")
+
+        if self.transcript_format == TranscriptFormat.TEXT:
+            return [
+                Document(
+                    page_content=transcript.text, metadata=transcript.json_response
+                )
+            ]
+        elif self.transcript_format == TranscriptFormat.SENTENCES:
+            sentences = transcript.get_sentences()
+            return [
+                Document(page_content=s.text, metadata=s.dict(exclude={"text"}))
+                for s in sentences
+            ]
+        elif self.transcript_format == TranscriptFormat.PARAGRAPHS:
+            paragraphs = transcript.get_paragraphs()
+            return [
+                Document(page_content=p.text, metadata=p.dict(exclude={"text"}))
+                for p in paragraphs
+            ]
+        elif self.transcript_format == TranscriptFormat.SUBTITLES_SRT:
+            return [Document(page_content=transcript.export_subtitles_srt())]
+        elif self.transcript_format == TranscriptFormat.SUBTITLES_VTT:
+            return [Document(page_content=transcript.export_subtitles_vtt())]
+        else:
+            raise ValueError("Unknown transcript format.")