fix(premium): cache updating workflow was broken

Author: Xephi

authme-core/src/main/java/fr/xephi/authme/service/PremiumService.java

@@ -268,7 +268,9 @@ public void performCleanup() {
 
     /**
      * Finalizes a pending premium verification: saves the confirmed Mojang UUID to the database,
-     * updates the player cache, notifies the proxy, and sends a success message to the player.
+     * notifies the proxy, and sends a success message to the player.
+     * Does NOT update the player cache — the player is not yet logged in at this point;
+     * the subsequent forceLogin() call will add them to the cache once authentication completes.
      * Must be called from an async context.
      *
      * @param player        the player whose premium status is being confirmed
@@ -284,13 +286,20 @@ public void finalizePendingPremium(Player player, UUID confirmedUuid) {
             logger.warning("Could not finalize pending premium for " + playerName + ": no auth record found");
             return;
         }
-        storePremiumUuid(auth, confirmedUuid, player, playerName);
+        storePremiumUuid(auth, confirmedUuid, player, playerName, false);
     }
 
     private void storePremiumUuid(PlayerAuth auth, UUID uuid, CommandSender feedbackTarget, String playerName) {
+        storePremiumUuid(auth, uuid, feedbackTarget, playerName, true);
+    }
+
+    private void storePremiumUuid(PlayerAuth auth, UUID uuid, CommandSender feedbackTarget, String playerName,
+                                   boolean updateCache) {
         auth.setPremiumUuid(uuid);
         if (dataSource.updatePremiumUuid(auth)) {
-            playerCache.updatePlayer(auth);
+            if (updateCache) {
+                playerCache.updatePlayer(auth);
+            }
             bungeeSender.sendPremiumSet(playerName);
             messages.send(feedbackTarget, MessageKey.PREMIUM_ENABLE_SUCCESS);
         } else {