fix(renderer): 修复动画帧延迟计算

- 使用 saturating_sub避免负数结果
- 确保计算结果不会溢出
- 提高代码的健壮性和可靠性

Author: yyxxryrx

src/display/renderer.rs

@@ -104,15 +104,23 @@ pub fn render_video(results: Vec<(ImageProcessorResult, usize)>, config: Config)
             let time = std::time::Instant::now();
             print!("\x1b[0;0H");
             println!("{}", frame);
-            std::thread::sleep(Duration::from_micros(delay - (time.elapsed().as_micros() as u64) - config.fps.pow(2)));
+            std::thread::sleep(Duration::from_micros(
+                delay
+                    .saturating_sub(time.elapsed().as_micros() as u64)
+                    .saturating_sub(config.fps.pow(2)),
+            ));
         }
     } else {
         for frame in frames {
             // As same as above
             let time = std::time::Instant::now();
             print!("\x1b[0;0H");
             println!("{}", frame);
-            std::thread::sleep(Duration::from_micros(delay - (time.elapsed().as_micros() as u64) - config.fps.pow(2)));
+            std::thread::sleep(Duration::from_micros(
+                delay
+                    .saturating_sub(time.elapsed().as_micros() as u64)
+                    .saturating_sub(config.fps.pow(2)),
+            ));
         }
     }
 }