feat: Implement logic to prevent deletion of system tasks and rewards; update APIs and tests accordingly

frontend/vue-app/package-lock.json

@@ -23,6 +23,7 @@
         "@vue/tsconfig": "^0.8.1",
         "eslint": "^9.37.0",
         "eslint-plugin-vue": "~10.5.0",
+        "flush-promises": "^1.0.2",
         "jiti": "^2.6.1",
         "jsdom": "^27.0.1",
         "npm-run-all2": "^8.0.4",
@@ -3842,6 +3843,13 @@
       "dev": true,
       "license": "ISC"
     },
+    "node_modules/flush-promises": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/flush-promises/-/flush-promises-1.0.2.tgz",
+      "integrity": "sha512-G0sYfLQERwKz4+4iOZYQEZVpOt9zQrlItIxQAAYAWpfby3gbHrx0osCHz5RLl/XoXevXk0xoN4hDFky/VV9TrA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/foreground-child": {
       "version": "3.3.1",
       "resolved": "https://registry.npmjs.org/foreground-child/-/foreground-child-3.3.1.tgz",