feat(mail) : install dompurify + types

frontend/package.json

@@ -19,6 +19,7 @@
         "@tailwindcss/typography": "^0.5.19",
         "@vuepic/vue-datepicker": "^12.1.0",
         "chart.js": "^4.5.1",
+        "dompurify": "^3.4.5",
         "marked": "^18.0.0",
         "nuxt": "^4.3.1",
         "nuxt-toast": "^1.4.0",
@@ -27,5 +28,8 @@
         "vue-advanced-cropper": "^2.8.9",
         "vue-chartjs": "^5.3.3",
         "vue-router": "^4.6.4"
+    },
+    "devDependencies": {
+        "@types/dompurify": "^3.0.5"
     }
 }