Problem Statement

Currently, CRI-O only supports traditional (forward) port forwarding where the
host connects to a port in the container. There are scenarios where it's useful
to have the reverse: a listener in the container that forwards connections back
to the host.

Use Cases

1. Development Workflows: Allow containerized applications to connect to
   databases or services running on the developer's host machine without
   complex network configuration.

2. IDE Debugging: Enable containers to connect back to debugger interfaces
   running on the host (e.g., Java remote debugging, Python debugpy).

3. Service Mesh Testing: Test service mesh proxies that need to connect to
   control plane components on the host.

4. CI/CD Pipelines: Allow test containers to access mock services or test
   fixtures running on the CI runner.

Proposed Solution

Implement reverse port forwarding that:

• Creates a TCP listener in the container's network namespace
• Waits for the container to connect to localhost:port
• Forwards the connection back to the host stream
• Is controlled via a pod annotation: io.cri-o.reverse-ports: "8080,9090"