feat: email client prototype

frontend/app/package.json

@@ -106,7 +106,9 @@
     "ngx-markdown": "17.1.1",
     "ngx-moment": "6.0.2",
     "opening_hours": "3.8.0",
+    "pkijs": "3.1.0",
     "pmtiles": "3.0.3",
+    "postal-mime": "2.2.5",
     "rxjs": "7.8.1",
     "semver": "7.6.0",
     "swiper": "8.4.5",
@@ -139,6 +141,7 @@
     "@ionic/cli": "7.2.0",
     "@openstapps/prettier-config": "workspace:*",
     "@openstapps/tsconfig": "workspace:*",
+    "@types/dompurify": "^3.0.5",
     "@types/fontkit": "2.0.7",
     "@types/geojson": "1.0.6",
     "@types/glob": "8.1.0",
@@ -154,6 +157,7 @@
     "@typescript-eslint/parser": "7.2.0",
     "cordova-res": "0.15.4",
     "cypress": "13.7.0",
+    "dompurify": "^3.1.6",
     "eslint": "8.57.0",
     "eslint-plugin-jsdoc": "48.2.1",
     "eslint-plugin-prettier": "5.1.3",