[Cleanup] Remove code duplication + concat function to reduce bin size

src/_Plugin_Helper.cpp

@@ -18,9 +18,7 @@ PluginTaskData_base *Plugin_task_data[TASKS_MAX] = { nullptr, };
 
 String PCONFIG_LABEL(int n) {
   if (n < PLUGIN_CONFIGVAR_MAX) {
-    String result = F("pconf_");
-    result += n;
-    return result;
+    return concat(F("pconf_"), n);
   }
   return F("error");
 }
@@ -67,6 +65,11 @@ void initPluginTaskData(taskIndex_t taskIndex, PluginTaskData_base *data) {
       }
     }
 #endif
+#if FEATURE_PLUGIN_FILTER
+// TODO TD-er: Implement init
+
+#endif
+
   } else if (data != nullptr) {
     delete data;
   }
@@ -88,10 +91,11 @@ bool pluginTaskData_initialized(taskIndex_t taskIndex) {
 }
 
 String getPluginCustomArgName(int varNr) {
-  String argName = F("pc_arg");
+  return getPluginCustomArgName(F("pc_arg"), varNr);
+}
 
-  argName += varNr + 1;
-  return argName;
+String getPluginCustomArgName(const __FlashStringHelper * label, int varNr) {
+  return concat(label, varNr + 1);
 }
 
 int getFormItemIntCustomArgName(int varNr) {
@@ -117,8 +121,8 @@ void pluginWebformShowValue(taskIndex_t   taskIndex,
   }
 
   pluginWebformShowValue(
-    label, String(F("valuename_")) + taskIndex + '_' + varNr,
-    value, String(F("value_")) + taskIndex + '_' + varNr,
+    label, concat(F("valuename_"), taskIndex) + '_' + varNr,
+    value, concat(F("value_"), taskIndex) + '_' + varNr,
     addTrailingBreak);
 }