add core revenue to model and allow to tweak params

hub/services/static/js/roi-calculator/roi-calculator-app.js

@@ -198,6 +198,18 @@ class ROICalculatorApp {
         }
     }
 
+    updateCoreServiceRevenue(value) {
+        try {
+            const element = document.getElementById('core-service-revenue');
+            if (element) {
+                element.value = value;
+                this.updateCalculations();
+            }
+        } catch (error) {
+            console.error('Error updating core service revenue:', error);
+        }
+    }
+
     updateScenarioChurn(scenarioKey, churnRate) {
         try {
             if (this.calculator && this.calculator.scenarios[scenarioKey]) {