refactor: 时间选择逻辑下沉至 Dialog、Worker 模板方法抽象、配置访问安全化与代码风格统一

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/gui/ALAutoScriptOrchDialog/_helpers.py

@@ -204,11 +204,11 @@ class _DateOffsetContainer(QWidget):
         val = self._spinBox.value()
         unit = self._unitCombo.currentData()
         if unit == "weeks":
-            return val * 7
+            return val*7
         if unit == "months":
-            return val * 30
+            return val*30
         if unit == "years":
-            return val * 365
+            return val*365
         return val