feat(ui_builders_controls): scaffold module imports and constants

scanslicer/ui_builders_controls.py

@@ -0,0 +1,16 @@
+from PySide6.QtCore import QSize, Qt
+from PySide6.QtWidgets import (
+    QCheckBox,
+    QComboBox,
+    QGridLayout,
+    QHBoxLayout,
+    QLabel,
+    QPushButton,
+    QSpinBox,
+    QWidget,
+)
+
+from .ui_builders_shared import ScanSlicerUiSharedMixin, ScrollbarWheelOnlyScrollArea, icon_from_svg_data_url
+
+
+# ScanSlicerUiControlsMixin: class definition for ScanSlicer behavior.