clarify what getEntityId actually returns (#10839)

patches/api/Fix-upstream-javadocs.patch

@@ -381,6 +381,26 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
           * the portal, it will fly to it before mounting.
           */
          LAND_ON_PORTAL,
+diff --git a/src/main/java/org/bukkit/entity/Entity.java b/src/main/java/org/bukkit/entity/Entity.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/entity/Entity.java
++++ b/src/main/java/org/bukkit/entity/Entity.java
+@@ -0,0 +0,0 @@ public interface Entity extends Metadatable, CommandSender, Nameable, Persistent
+     public List<org.bukkit.entity.Entity> getNearbyEntities(double x, double y, double z);
+ 
+     /**
+-     * Returns a unique id for this entity
++     * Returns the network protocol ID for this entity. This is
++     * not to be used as an identifier for the entity except in
++     * network-related operations. Use {@link #getUniqueId()} as
++     * an entity identifier instead.
+      *
+-     * @return Entity id
++     * @return the network protocol ID
++     * @see #getUniqueId()
+      */
+     public int getEntityId();
+ 
 diff --git a/src/main/java/org/bukkit/entity/HumanEntity.java b/src/main/java/org/bukkit/entity/HumanEntity.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/entity/HumanEntity.java