cmd/cli: fix validating remote custom config

Currently, custom config is only validated against invalid syntax, not
the validating rules for each configuration value. It causes ctrld
process fatal instead of disregarding as expected.

To fix this, force the validating rule after fetching remote config.
While at it, also add the default network value if non-existed.

cmd/cli/prog.go

@@ -359,6 +359,7 @@ func (p *prog) apiConfigReload() {
 				return
 			}
 			setListenerDefaultValue(cfg)
+			setNetworkDefaultValue(cfg)
 			logger.Debug().Msg("custom config changes detected, reloading...")
 			p.apiReloadCh <- cfg
 		} else {