Set green LED at start when filament loaded + set Idler as idle at start

src/main.cpp

@@ -117,6 +117,11 @@ void setup() {
     // Idler and Selector decide whether homing is possible/safe
     mi::idler.Init();
     ms::selector.Init();
+
+    // activate the correct LED if filament is present
+    if (mg::globals.FilamentLoaded() > mg::FilamentLoadState::AtPulley) {
+        ml::leds.SetMode(mg::globals.ActiveSlot(), ml::green, ml::on);
+    }
 }
 
 static constexpr const uint8_t maxMsgLen = 10;

src/modules/idler.cpp

@@ -123,8 +123,8 @@ void Idler::Init() {
         // home the Idler only in case we don't have filament loaded in the printer (or at least we think we don't)
         PlanHome(mm::Idler);
     } else {
-        // otherwise set selector's position according to know slot positions (and pretend it is correct)
-        mm::motion.SetPosition(mm::Idler, SlotPosition(mg::globals.ActiveSlot()).v);
+        // otherwise assume the Idler is at its idle position (that's where it usually is)
+        mm::motion.SetPosition(mm::Idler, SlotPosition(IdleSlotIndex()).v);
         InvalidateHoming(); // and plan homing sequence ASAP
     }
 }