cmd/cli: use warn level for network changes logging

So these events will be recorded separately from normal runtime log,
making troubleshooting later more easily.

While at it, only update ctrld.ProxyLogger for runCmd, it's the only one
which needs to log the query when proxying requests.

cmd/cli/cli.go

@@ -267,6 +267,8 @@ func run(appCallback *AppCallback, stopCh chan struct{}) {
 	// Log config do not have thing to validate, so it's safe to init log here,
 	// so it's able to log information in processCDFlags.
 	logWriters := initLogging()
+	// TODO: find a better way.
+	ctrld.ProxyLogger.Store(mainLog.Load())
 
 	// Initializing internal logging after global logging.
 	p.initInternalLogging(logWriters)