Define MAXLIMIT to prevent unreadable numbers.

Define MAXLIMIT to prevent unreadable numbers.

Look for where numbers are displayed or processed in the calculator code, likely in the main Kivy UI files or calculation logic. Define a constant MAXLIMIT to cap numeric values, preventing overflow or unreadable displays. Test by entering large numbers to see the current behavior and verify the limit applies correctly.

索引モデルが issue の本文から書いたものです。