[Fargate] [request]: cloudwatch metric or container stats for open connections (e.g. "conntrack")

It would be great if we could get some "conntrack" metrics for ECS/Fargate, either via cloudwatch metrics (containerinsights) or via the container-stats metadata endpoint (which could then be processed by another agent, such as datadog).

In our use case, especially having insights into "open connections" it would allow us to track if applications are leaking connections (could also be interesting for file descriptors?), and/or setting up alarms, especially if there are certain limits on those.

No repository files, tests, or implementation entry points are named. Start by determining whether ECS/Fargate should expose conntrack and file-descriptor data through CloudWatch Container Insights or the container-stats metadata endpoint. Done would require an agreed metric surface and a documented implementation path.

Written by the indexing model from the issue text.