node_config: load() returns true on parse success; main: specific diagnostics per missing field

tools/chatgui/src/main.cpp

@@ -42,11 +42,16 @@ int main(int argc, char *argv[]) {
         }
     } else {
         if (!cfg.load()) {
-            qCritical("Failed to load config: %s", qPrintable(cfgPath));
+            qCritical("Cannot open/read config file: %s", qPrintable(cfgPath));
             return 1;
         }
-        if (cfg.privKey().length() != 64 || cfg.pubKey().length() != 64 ||
-            cfg.nodeId().length() != 16) {
+        if (cfg.privKey().length() != 64 || cfg.pubKey().length() != 64) {
+            qWarning("Config: keys missing/invalid, regenerating identity");
+            cfg.generateIdentity();
+            needSave = true;
+        }
+        if (cfg.nodeId().length() != 16) {
+            qWarning("Config: my_node_id missing/invalid, regenerating identity");
             cfg.generateIdentity();
             needSave = true;
         }