Adding the Kit interface [https://github.com/tmc/langchaingo/issues/1103]

[amritsingh183]

Checkout #1103

This PR implements the Kit interface which can help standardize the usage of the functionality offered by this interface i-e a convenient way (for third party tool providers or even if you want use it yourself in your code) of making a group of tools (Kit) available to the agent

• Read the Contributing documentation.
• Read the Code of conduct documentation.
• Name your Pull Request title clearly, concisely, and prefixed with the name of the primarily affected package you changed according to Good commit messages (such as memory: add interfaces for X, Y or util: add whizzbang helpers).
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. Fixes #123).
• Describes the source of new concepts.
• References existing implementations as appropriate.
• Contains test coverage for new functions.
• Passes all golangci-lint checks.

[amritsingh183]

@FluffyKebab I have addressed your feedback, please review the changed code