willexecutors: fee-bound is_valid (extremes allowed), is_selected flag-only; fix merge_will crash on missing date_to_check; DNSSEC async, ical folding, pyright/ruff cleanup; refresh karen7/samanta7 fixtures

bal/gui/qt/widgets.py

@@ -18,10 +18,15 @@ Contents:
     * WillWidget                                            - single will-tx box
 """
 
+from typing import TYPE_CHECKING
+
 from .calendar import BalCalendar, BalCalendarButton
 from .common import *
 from .common import _, _logger  # underscore names are not re-exported by "import *"
 
+if TYPE_CHECKING:
+    from .window import BalWindow
+
 
 def compute_reminder_offsets(days, count):
     """Return the reminder offsets (in days BEFORE the deadline) for an .ics event.