[Docs] Document TappedOutInterface::analyzeDeck lifecycle (#7887)

cockatrice/src/client/network/interfaces/tapped_out_interface.h

@@ -40,6 +40,12 @@ private slots:
 
 public:
     explicit TappedOutInterface(QObject *parent = nullptr);
+    /**
+     * Posts the deck for analysis and returns immediately; there is no signal for the
+     * outcome. The result opens in the browser or an error dialog, after which the
+     * interface deletes itself, so a caller must call this once and not keep or reuse
+     * the pointer afterwards.
+     */
     void analyzeDeck(const DeckList &deck);
 };