Fix message listener

app/server.js

@@ -128,9 +128,9 @@ app.event("message", async ({ event, client, context }) => {
             options: categories.map((category) => ({
               text: {
                 type: "plain_text",
-                text: category,
+                text: category,  // This is the display text for the option
               },
-              value: category,
+              value: createCategoryIdentifier(category),  // This is the value sent when the option is selected
             })),
           },
         },
@@ -335,4 +335,12 @@ async function generateIncByCategoryChart(numberOfDays){
   chart.setWidth(800);
   chart.setHeight(400);
   return chart.getUrl();
+}
+
+// Function to create a unique identifier from a category name
+function createCategoryIdentifier(categoryName) {
+  return categoryName
+    .toLowerCase()        // Convert to lowercase
+    .replace(/\s+/g, '-') // Replace spaces with hyphens
+    .replace(/[^\w-]/g, ''); // Remove any non-alphanumeric characters except hyphens
 }