The netstat-based parser matched the literal English "LISTENING"
state string, which is translated on non-English Windows (e.g.
"ABHÖREN", "ÉCOUTE", "ESCUTANDO"). On those systems the regex matched
zero lines, so killProcessOnPort silently did nothing -- fail-open,
not a regression, but ineffective for the exact users the fix targets.
Replace it with `Get-NetTCPConnection -State Listen -LocalPort <port>`,
which reads the same underlying WinNT API netstat's display layer
translates, so it's unaffected by OS display language. Verified
against a real listening port on this machine (matched the actual
owning PID).
Also fixed a stale duplicate of the "killProcessOnPort is a no-op on
Windows" comment left behind in server/index.js.