Now that NODE-6923 has been completed, https://github.com/langchain-ai/langchainjs should be updated with proper wrapping metadata that captures library/version.

At the same time we can clean up the documented examples that include driverInfo as part of the example, as this would be superfluous.

The driver version used by Langchain would need to be updated to ensure the appropriate API is available.

AC:

• Expose db from the Collection object in the driver
• Expose client from the Db object in the driver
• Use collection.db.client.appendMetadata() in langchain to add the driver info.

Testing AC:

• Attempt to spy on the mongo client in vectorstores.int.test.ts to ensure appendMetadata has been called with the appropriate driver info