feat: Add unit invitation code functionality and user verification using code

package-lock.json

@@ -28,6 +28,7 @@
         "helmet": "^7.1.0",
         "ioredis": "^5.3.2",
         "morgan": "^1.10.0",
+        "nanoid": "^5.0.7",
         "nodemailer": "^6.9.10",
         "passport-jwt": "^4.0.1",
         "pg": "^8.11.3",
@@ -7165,6 +7166,23 @@
         "thenify-all": "^1.0.0"
       }
     },
+    "node_modules/nanoid": {
+      "version": "5.0.7",
+      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-5.0.7.tgz",
+      "integrity": "sha512-oLxFY2gd2IqnjcYyOXD8XGCftpGtZP2AbHbOkthDkvRywH5ayNtPVy9YlOPcHckXzbLTCHpkb7FB+yuxKV13pQ==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/ai"
+        }
+      ],
+      "bin": {
+        "nanoid": "bin/nanoid.js"
+      },
+      "engines": {
+        "node": "^18 || >=20"
+      }
+    },
     "node_modules/natural-compare": {
       "version": "1.4.0",
       "resolved": "https://registry.npmjs.org/natural-compare/-/natural-compare-1.4.0.tgz",