fix: add random_loop_range validation in VideoItem

- Validate that random_loop_range values are positive
- Validate that min <= max in random_loop_range
- Prevents invalid config from causing runtime panics in rand::gen_range

src/core/config.rs

@@ -503,6 +503,15 @@ impl VideoItem {
             }
         }
 
+        if let Some([min, max]) = self.random_loop_range {
+            if min <= 0 || max <= 0 {
+                bail!("{section}.random_loop_range 值必须大于 0");
+            }
+            if min > max {
+                bail!("{section}.random_loop_range[0] 不能大于 random_loop_range[1]");
+            }
+        }
+
         Ok(())
     }
 }