fix(FastSense): handle single-point thresholds in addSensor

When a resolved threshold has only 1 point (e.g. from a single-state
condition), addThreshold misinterpreted it as scalar form because
numel(X) <= 1. Use the scalar addThreshold(value, ...) form for
single-point thresholds to avoid passing Y as a name-value key.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: HanSur94

libs/FastSense/FastSense.m

@@ -575,12 +575,23 @@ function addSensor(obj, sensor, varargin)
                         thLabel = sprintf('Threshold %d', i);
                     end
                     [thColor, thStyle] = obj.resolveThresholdStyle(th.Color, th.LineStyle);
-                    obj.addThreshold(th.X, th.Y, ...
-                        'Direction', th.Direction, ...
-                        'ShowViolations', true, ...
-                        'Label', thLabel, ...
-                        'Color', thColor, ...
-                        'LineStyle', thStyle);
+                    if numel(th.X) <= 1
+                        % Single-point or scalar — use scalar form
+                        thVal = th.Y(1);
+                        obj.addThreshold(thVal, ...
+                            'Direction', th.Direction, ...
+                            'ShowViolations', true, ...
+                            'Label', thLabel, ...
+                            'Color', thColor, ...
+                            'LineStyle', thStyle);
+                    else
+                        obj.addThreshold(th.X, th.Y, ...
+                            'Direction', th.Direction, ...
+                            'ShowViolations', true, ...
+                            'Label', thLabel, ...
+                            'Color', thColor, ...
+                            'LineStyle', thStyle);
+                    end
                 end
             end
         end