chore(16-01): install mailparser + linkify-it for EML parsing

- mailparser 3.9.14 (RFC822/MIME parsing, sha256 attachment checksums)
- linkify-it 6.0.0 (URL extraction for phishing evidence)
- @types/mailparser devDependency (mailparser ships no bundled types)
- Verified: only these deps added (git diff package.json clean check)

package.json

@@ -40,7 +40,9 @@
     "date-fns": "^4.1.0",
     "dotenv": "^17.2.3",
     "ioredis": "^5.9.0",
+    "linkify-it": "^6.0.0",
     "lucide-react": "^0.562.0",
+    "mailparser": "^3.9.14",
     "next": "16.1.1",
     "next-themes": "^0.4.6",
     "node-cron": "^4.2.1",
@@ -62,6 +64,7 @@
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4.1.18",
+    "@types/mailparser": "^3.4.6",
     "@types/node": "^20.19.27",
     "@types/nodemailer": "^7.0.4",
     "@types/pg": "^8.16.0",