Tool Proposal: Add Shell tools for Python Langchain Parity

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Checked

• I searched existing ideas and did not find a similar one
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• I've clearly described the feature request and motivation for it

Feature request

Add a Shell Tool to LangChain.js to match the existing Python capabilities, enabling JavaScript users to execute shell commands or scripts directly within LangChain workflows for better agentic behaviour.

Motivation

The addition of a shell tool to LangChain.js would fill a critical gap, making it more versatile for developers using JavaScript in production. Currently, LangChain's Python shell tool allows developers to interact with the command line, enabling workflows that involve external data handling, system administration tasks, or integration with other CLI-based applications. Having these capabilites missing from the JS package, I feel, significantly damages the "agentic" behaviour langchain aspires towards.

Proposal (If applicable)

Create functionally equivalent implementations of:
langchain_community.tools.shell.tool.ShellInput and langchain_community.tools.shell.tool.ShellTool
For the JS langchain packages.

As we're a UofT team like many others, we'd like to work on this if it's acceptable to the maintainers.

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@jacoblee93 From what I can tell, there is no way to do this presently in JS. Is this worth making an issue out of and getting started on implementing?