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/gitlab/prompt.py

@@ -0,0 +1,70 @@
+# flake8: noqa
+GET_ISSUES_PROMPT = """
+This tool will fetch a list of the repository's issues. It will return the title, and issue number of 5 issues. It takes no input.
+"""
+
+GET_ISSUE_PROMPT = """
+This tool will fetch the title, body, and comment thread of a specific issue. **VERY IMPORTANT**: You must specify the issue number as an integer.
+"""
+
+COMMENT_ON_ISSUE_PROMPT = """
+This tool is useful when you need to comment on a GitLab issue. Simply pass in the issue number and the comment you would like to make. Please use this sparingly as we don't want to clutter the comment threads. **VERY IMPORTANT**: Your input to this tool MUST strictly follow these rules:
+
+- First you must specify the issue number as an integer
+- Then you must place two newlines
+- Then you must specify your comment
+"""
+CREATE_PULL_REQUEST_PROMPT = """
+This tool is useful when you need to create a new pull request in a GitLab repository. **VERY IMPORTANT**: Your input to this tool MUST strictly follow these rules:
+
+- First you must specify the title of the pull request
+- Then you must place two newlines
+- Then you must write the body or description of the pull request
+
+To reference an issue in the body, put its issue number directly after a #.
+For example, if you would like to create a pull request called "README updates" with contents "added contributors' names, closes issue #3", you would pass in the following string:
+
+README updates
+
+added contributors' names, closes issue #3
+"""
+CREATE_FILE_PROMPT = """
+This tool is a wrapper for the GitLab API, useful when you need to create a file in a GitLab repository. **VERY IMPORTANT**: Your input to this tool MUST strictly follow these rules:
+
+- First you must specify which file to create by passing a full file path (**IMPORTANT**: the path must not start with a slash)
+- Then you must specify the contents of the file
+
+For example, if you would like to create a file called /test/test.txt with contents "test contents", you would pass in the following string:
+
+test/test.txt
+
+test contents
+"""
+
+READ_FILE_PROMPT = """
+This tool is a wrapper for the GitLab API, useful when you need to read the contents of a file in a GitLab repository. Simply pass in the full file path of the file you would like to read. **IMPORTANT**: the path must not start with a slash
+"""
+
+UPDATE_FILE_PROMPT = """
+This tool is a wrapper for the GitLab API, useful when you need to update the contents of a file in a GitLab repository. **VERY IMPORTANT**: Your input to this tool MUST strictly follow these rules:
+
+- First you must specify which file to modify by passing a full file path (**IMPORTANT**: the path must not start with a slash)
+- Then you must specify the old contents which you would like to replace wrapped in OLD <<<< and >>>> OLD
+- Then you must specify the new contents which you would like to replace the old contents with wrapped in NEW <<<< and >>>> NEW
+
+For example, if you would like to replace the contents of the file /test/test.txt from "old contents" to "new contents", you would pass in the following string:
+
+test/test.txt
+
+This is text that will not be changed
+OLD <<<<
+old contents
+>>>> OLD
+NEW <<<<
+new contents
+>>>> NEW
+"""
+
+DELETE_FILE_PROMPT = """
+This tool is a wrapper for the GitLab API, useful when you need to delete a file in a GitLab repository. Simply pass in the full file path of the file you would like to delete. **IMPORTANT**: the path must not start with a slash
+"""