fix(ui): preserve auto-connect state when navigating back from character screen

Add resetForBack() to RealmScreen that clears selection state without
resetting autoSelectAttempted, preventing single-realm auto-connect from
re-firing when the user navigates back from the character screen.

Signed-off-by: Pavel Okhlopkov <pavel.okhlopkov@flant.com>

include/ui/realm_screen.hpp

@@ -44,6 +44,18 @@ public:
         statusMessage.clear();
     }
 
+    /**
+     * Reset for back-navigation from character screen.
+     * Preserves autoSelectAttempted so single-realm auto-connect doesn't re-fire.
+     */
+    void resetForBack() {
+        selectedRealmIndex = -1;
+        realmSelected = false;
+        selectedRealmName.clear();
+        selectedRealmAddress.clear();
+        statusMessage.clear();
+    }
+
     /**
      * Check if a realm has been selected
      */

src/core/ui_screen_callback_handler.cpp

@@ -155,7 +155,7 @@ void UIScreenCallbackHandler::setupCallbacks() {
     uiManager_.getCharacterScreen().setOnBack([this]() {
         // Disconnect from world server and reset UI state for fresh realm selection
         gameHandler_.disconnect();
-        uiManager_.getRealmScreen().reset();
+        uiManager_.getRealmScreen().resetForBack();
         uiManager_.getCharacterScreen().reset();
         setState_(AppState::REALM_SELECTION);
     });