added round to 3 decimals for API JSON (reduced transmitted length)

tools/esp8266/webApi.cpp

@@ -281,7 +281,7 @@ void webApi::getLive(JsonObject obj) {
             obj2[F("ch_names")][0] = "AC";
             for (uint8_t fld = 0; fld < 11; fld++) {
                 pos = (iv->getPosByChFld(CH0, list[fld], rec));
-                ch0[fld] = (0xff != pos) ? iv->getValue(pos, rec) : 0.0;
+                ch0[fld] = (0xff != pos) ? round3(iv->getValue(pos, rec)) : 0.0;
                 obj[F("ch0_fld_units")][fld] = (0xff != pos) ? String(iv->getUnit(pos, rec)) : F("n/a");
                 obj[F("ch0_fld_names")][fld] = (0xff != pos) ? String(iv->getFieldName(pos, rec)) : F("n/a");
             }
@@ -298,7 +298,7 @@ void webApi::getLive(JsonObject obj) {
                         case 4:  pos = (iv->getPosByChFld(j, FLD_YT, rec));  break;
                         case 5:  pos = (iv->getPosByChFld(j, FLD_IRR, rec)); break;
                     }
-                    cur[k] = (0xff != pos) ? iv->getValue(pos, rec) : 0.0;
+                    cur[k] = (0xff != pos) ? round3(iv->getValue(pos, rec)) : 0.0;
                     if(1 == j) {
                         obj[F("fld_units")][k] = (0xff != pos) ? String(iv->getUnit(pos, rec)) : F("n/a");
                         obj[F("fld_names")][k] = (0xff != pos) ? String(iv->getFieldName(pos, rec)) : F("n/a");

tools/esp8266/webApi.h

@@ -41,6 +41,10 @@ class webApi {
 
         Inverter<> *getInverter(DynamicJsonDocument jsonIn, JsonObject jsonOut);
 
+        double round3(double value) {
+           return (int)(value * 1000 + 0.5) / 1000.0;
+        }
+
         AsyncWebServer *mSrv;
         app *mApp;