Only regenerate verify codes on broadcast, not any targeted /chat

Any /chat {agent-id} {code} was previously exempted only if aimed at
the code's rightful owner; sending to the wrong player still burned
it. Now only an untargeted, open-chat broadcast counts as a leak -
mistargeting via /chat is harmless.

src/Game/Service/GameResponseService.php

@@ -460,10 +460,9 @@ class GameResponseService
                 continue;
             }
 
-            // Sending a code privately to its rightful recipient via /chat {agent-id}
-            // is the whole point of this puzzle - only a leak (broadcast, or sent to
-            // the wrong player) should regenerate it.
-            if ($sendTo === (int)$targetPlayerScreen) {
+            // Sending a code via a targeted /chat {agent-id} is fine, even to the
+            // wrong player - only broadcasting it in the open chat is a real leak.
+            if ($sendTo !== 0) {
                 continue;
             }