Investigate Possible New Metrics for Stopping Long Running Transactions

1. Identify new metrics that could be used to indicate the necessity of stopping long-running transactions.
2. Evaluate how they can be implemented in WT and used by Server.
3. Implement the chosen metric as part of this ticket.

The goal is to identify a clear and effective way to detect when long-running transactions should be stopped (rolled back or committed) and incorporate that metric into WiredTiger.