Many improvements to chunk prioritization and bug fixes

Fixed a few bugs, and made numerous improvements.
Fixed issue where a sync chunk load could have its ticket removed and the
priority ticket could expire...
Still not perfect there but better than before.

Also fixed few other misc issues such as watchdog cpu usage, chunk queue update
had risk of double enqueue due to it no longer being a set.

Added much more information about chunk state to watchdog prints.

I see some more room for improvement even, but this is much better than before.

Fixes #3407
Fixes #3411
Fixes #3395
Fixes #3389

Spigot-Server-Patches/Optimize-isOutsideRange-to-use-distance-maps.patch

@@ -16,8 +16,8 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 -    private final ChunkMapDistance.b f = new ChunkMapDistance.b(8);
 +    public static final int MOB_SPAWN_RANGE = 8; //private final ChunkMapDistance.b f = new ChunkMapDistance.b(8); // Paper - no longer used
      private final ChunkMapDistance.c g = new ChunkMapDistance.c(33);
-     private final java.util.Queue<PlayerChunk> pendingChunkUpdates = new java.util.ArrayDeque<>(); // PAIL pendingChunkUpdates // Paper - use a queue
-     private final ChunkTaskQueueSorter i;
+     // Paper start use a queue, but still keep unique requirement
+     public final java.util.Queue<PlayerChunk> pendingChunkUpdates = new java.util.ArrayDeque<PlayerChunk>() {
 @@ -0,0 +0,0 @@ public abstract class ChunkMapDistance {
      private final Executor m;
      private long currentTick;