fix(clamps): judge tiny keep-outs tolerance-free in interactive fill

InteractiveClamps.MaterialInKeepOut flattened a sub-tolerance keep-out with
the 0.001 polygon tolerance and called a part covering a 1e-5 clamp clear,
so the fill safety net could pass it. Keep-outs below the tolerance now use
KeepOutOverlap. Adds the 1e-5 zone sweep through every fill strategy and a
push (characterization; both already stay clear).

PM b0062c73-40ef-440e-8efb-b94908f7c2d1

OpenNest.Engine/Jobs/InteractiveClamps.cs

@@ -97,6 +97,11 @@ internal static class InteractiveClamps
         var partProfile = new ShapeProfile(PartGeometry.GetPartEntities(part));
         if (partProfile.Perimeter == null)
             return true;
+        // A keep-out below the polygon tolerance collapses in the tolerant test and would
+        // read as clear (PM b0062c73); judge it tolerance-free instead.
+        if (KeepOutOverlap.NeedsToleranceFreeTest(keepOut))
+            return KeepOutOverlap.MaterialEnters(partProfile.Perimeter.ToPolygonWithTolerance(0.001),
+                HolePolygons(partProfile), keepOut);
         var zoneProfile = new ShapeProfile(RectangleEntities(keepOut));
         if (zoneProfile.Perimeter == null)
             return true;