Implement transaction_name_groups config

[felixbarny]

The Node.js agent supports the usePathAsTransactionName option.

A risk of using this option is that it can lead to cardinality issues when the path contains parameters. To mitigate this, the Node.js agent should

• Implement the transaction_name_groups option
• Add a warning to the usePathAsTransactionName docs, similar to the one from the Java agent.

[Siddhu545]

Hi! I’d like to take this issue.

The risk of high-cardinality transaction names when using usePathAsTransactionName is definitely something worth addressing. I’ll implement the transaction_name_groups option to allow users to group dynamic paths into normalized patterns, helping reduce cardinality in APM data. I’ll also update the documentation to include a warning, similar to what the Java agent does, to help guide users toward best practices.

Let me know if there's any direction or edge cases you'd like me to keep in mind!