Publish menus from the browser instead of scp

The admin signs in with the shared password, creates a Menu Set, drops photos
into it (shrunk in the browser first), reorders Pages by dragging or with
up/down buttons, previews the Draft exactly as customers would see it, and
publishes it over the previous set. Restore and delete close the loop. Mutations
need a session, a same-origin request and a CSRF token derived from the session;
a Draft's media is served only to a session holder.

package-lock.json

@@ -9,6 +9,7 @@
       "version": "0.1.0",
       "dependencies": {
         "@fastify/cookie": "^11.1.2",
+        "@fastify/formbody": "^9.0.0",
         "@fastify/multipart": "^10.1.2",
         "@fastify/static": "^10.1.4",
         "fastify": "^5.12.5",
@@ -146,6 +147,26 @@
         "fast-json-stringify": "^7.0.0"
       }
     },
+    "node_modules/@fastify/formbody": {
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/@fastify/formbody/-/formbody-9.0.0.tgz",
+      "integrity": "sha512-T/af26CSrUARBCvsEmv+DJLPfZlrRKESzqironxP1j7qzuLyKcoZtj6MuTGShuKx1THXugoie2oFbUJxXfGFzA==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fastify"
+        },
+        {
+          "type": "opencollective",
+          "url": "https://opencollective.com/fastify"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "fast-querystring": "^1.1.2",
+        "fastify-plugin": "^6.0.0"
+      }
+    },
     "node_modules/@fastify/forwarded": {
       "version": "3.0.2",
       "resolved": "https://registry.npmjs.org/@fastify/forwarded/-/forwarded-3.0.2.tgz",