Refactor energy clamp dialog to handle empty functions list gracefully

lib/pages/routines/widgets/routine_dialogs/power_clamp_enargy/energy_clamp_dialog.dart

@@ -99,7 +99,25 @@ class _EnergyClampDialogState extends State<EnergyClampDialog> {
               mainAxisSize: MainAxisSize.min,
               children: [
                 const DialogHeader('Energy Clamp Conditions'),
-                Expanded(child: _buildMainContent(context, state)),
+                Expanded(
+                    child: _functions.isEmpty
+                        ? SizedBox(
+                            child: Row(
+                              crossAxisAlignment: CrossAxisAlignment.center,
+                              mainAxisAlignment: MainAxisAlignment.center,
+                              children: [
+                                Center(
+                                    child: Text(
+                                  'You Cant add\n the Power Clamp to Then Section',
+                                  textAlign: TextAlign.center,
+                                  style: context.textTheme.bodyMedium!.copyWith(
+                                      color: ColorsManager.red,
+                                      fontWeight: FontWeight.w400),
+                                )),
+                              ],
+                            ),
+                          )
+                        : _buildMainContent(context, state)),
                 _buildDialogFooter(context, state),
               ],
             ),