Fix capital letter bug in windows

src/main.rs

@@ -414,6 +414,14 @@ fn handle_key(app: &mut App, key: KeyEvent) -> CalculatorResult<CalculatorRespon
             } => {
                 app.calculator.take_input(c)?;
             }
+            KeyEvent {
+                code: KeyCode::Char(c),
+                modifiers: KeyModifiers::SHIFT,
+            } => {
+                for c in c.to_uppercase() {
+                    app.calculator.take_input(c)?;
+                }
+            }
             _ => {}
         },
     }