Draft: flagSparseCross

flag all selected columns if some of these has nans. cross test, works horizontal.

saqc/core/modules/breaks.py

@@ -37,3 +37,8 @@ class Breaks(ModuleBase):
         **kwargs
     ) -> saqc.SaQC:
         return self.defer("flagJumps", locals())
+
+    def flagSparseCross(
+        self, field, fields, min_valid, flag=BAD, **kwargs
+    ) -> saqc.SaQC:
+        return self.defer("flagSparseCross", locals())