fix: update selected amount assignment in main page event handling

manager/display.lua

@@ -400,7 +400,7 @@ local function buildMainPage()
                 return true
 
             elseif event.type == 'amount_select' then
-                selectedAmount = event.amount
+                selectedAmount = event.button.amount
                 D.updateAmountButtons()
                 self:sync()
                 return true