Implement the basis for deleting player uuid data from storage

api/src/main/java/net/luckperms/api/model/user/UserManager.java

@@ -147,6 +147,17 @@ public interface UserManager {
      */
     @NonNull CompletableFuture<PlayerSaveResult> savePlayerData(@NonNull UUID uniqueId, @NonNull String username);
 
+    /**
+     * Deletes any data about a given player from the uuid caching system.
+     *
+     * <p>Note that this method does not affect any saved user/permissions data.</p>
+     *
+     * @param uniqueId the users mojang unique id
+     * @return a future encapsulating the result of the operation
+     * @since 5.2
+     */
+    @NonNull CompletableFuture<Void> deletePlayerData(@NonNull UUID uniqueId);
+
     /**
      * Gets a set all "unique" user UUIDs.
      *