small bindings fixes

utility-fx-controls/src/main/java/com/dua3/utility/fx/controls/SliderBuilder.java

@@ -4,7 +4,6 @@
 import javafx.beans.value.ObservableNumberValue;
 import javafx.geometry.Orientation;
 import javafx.scene.Node;
-import org.jspecify.annotations.Nullable;
 
 import java.util.function.BiFunction;
 import java.util.function.DoubleConsumer;
@@ -152,24 +151,13 @@ public SliderBuilder onChange(DoubleConsumer onChange) {
         return this;
     }
 
-    /**
-     * Binds the slider's value property to the specified observable number value.
-     *
-     * @param value the observable number value to which the slider's value property should be bound
-     * @return this instance of {@code SliderBuilder} for method chaining.
-     */
-    public SliderBuilder bind(ObservableNumberValue value) {
-        slider.valueProperty().bind(value);
-        return this;
-    }
-
     /**
      * Binds the slider's value property bidirectionally with the specified number property.
      *
      * @param value the property to be bound bidirectionally with the slider's value property.
      * @return this instance of {@code SliderBuilder} for method chaining.
      */
-    public SliderBuilder bindBidirectional(Property<@Nullable Number> value) {
+    public SliderBuilder bind(Property<Number> value) {
         slider.valueProperty().bindBidirectional(value);
         return this;
     }

utility-fx-controls/src/main/java/com/dua3/utility/fx/controls/TextFieldBuilder.java

@@ -93,6 +93,9 @@ public TextFieldBuilder type(TextFieldType type) {
      * @return this instance
      */
     public TextFieldBuilder bindDisabled(ObservableBooleanValue disabled) {
+        if (this.disabled != null) {
+            throw new IllegalStateException("the disabled property has already been bound to a value");
+        }
         this.disabled = disabled;
         return this;
     }