Bugfix for gif player WRT inactive segment and bugfix in copy FX

- if a segment is destroyed or turned inactive, disable the gif player: only one gif player instance can run at a time, if a inactive or destroyed segment uses it, the effect is broken for other segments.

- copy FX ironically copied the source segment on each call, should use reference not a copy!

wled00/FX.h

@@ -16,6 +16,10 @@
 bool canUseSerial(void);                        // WLEDMM implemented in wled_serial.cpp
 void strip_wait_until_idle(String whoCalledMe); // WLEDMM implemented in FX_fcn.cpp
 bool strip_uses_global_leds(void) __attribute__((pure));  // WLEDMM implemented in FX_fcn.cpp
+#ifdef WLED_ENABLE_GIF
+struct Segment;                                 // forward declaration
+void endImagePlayback(Segment *seg);            // implemented in image_loader.cpp
+#endif
 
 #define FASTLED_INTERNAL //remove annoying pragma messages
 #define USE_GET_MILLISECOND_TIMER
@@ -585,6 +589,9 @@ typedef struct Segment {
       #ifdef ARDUINO_ARCH_ESP32
       strip_wait_until_idle("~Segment()");
       #endif
+      #ifdef WLED_ENABLE_GIF
+      endImagePlayback(this);
+      #endif
 
       if ((Segment::_globalLeds == nullptr) && !strip_uses_global_leds() && (ledsrgb != nullptr)) {free(ledsrgb); ledsrgb = nullptr;}  // WLEDMM we need "!strip_uses_global_leds()" to avoid crashes (#104)
       if (name) { delete[] name; name = nullptr; }

wled00/FX_fcn.cpp

@@ -542,6 +542,9 @@ void Segment::setUp(uint16_t i1, uint16_t i2, uint8_t grp, uint8_t spc, uint16_t
 
   if (stop>start) markForBlank(); //turn old segment range off // WLEDMM stop > start // toDo: check if this can be skipped when boundsUnchanged
   if (i2 <= i1) { //disable segment
+    #ifdef WLED_ENABLE_GIF
+    endImagePlayback(this);
+    #endif
     stop = 0;
     markForReset();
     return;