dev tests fail if port 10100 is being used by another process #479
Description
Moonwall assumes that port 10100 is always available. If it isn't, it will try to start a node on that port, and that will succeed but the node will use a different port.
Can be detected by looking at this log line, it says 10100 but only for ipv6, for ipv4 it uses port 33011:
2025-06-12 11:23:27 Running JSON-RPC server: addr=127.0.0.1:33011,[::1]:10100
So moonwall should check if the port is available before starting the process. Optionally, it could try to parse the RPC port from logs, but that is more complicated and depends on the node, so it could be an optional feature.
To reproduce, run this in one terminal and moonwall on another:
nc -l -p 10100
pnpm moonwall test dev_frontier_template