Use a node package to install jquery-fileupload

Although the gem is called jquery-fileupload-rails, the node package is
called blueimp-file-upload.

Note we're using the same version as provided by the gem.

The jquery-fileupload gem provided a `basic.js` file (which we were
requiring), which had the following content:

```
//= require jquery-fileupload/vendor/jquery.ui.widget
//= require jquery-fileupload/jquery.iframe-transport
//= require jquery-fileupload/jquery.fileupload
``

This file isn't available in the Node.js package, so we're adapting its
contents in our application.js file. Since we're already requiring
jQuery UI widget, we're omitting that line.

package-lock.json

@@ -6,6 +6,7 @@
     "": {
       "name": "consuldemocracy",
       "dependencies": {
+        "blueimp-file-upload": "9.12.5",
         "foundation-sites": "^6.6.2",
         "jquery": "^3.7.1",
         "jquery-ui": "^1.13.2",
@@ -21,6 +22,11 @@
       "resolved": "https://registry.npmjs.org/argparse/-/argparse-2.0.1.tgz",
       "integrity": "sha512-8+9WqebbFzpX9OR+Wa6O29asIogeRMzcGtAINdpMHHyAg10f05aSFVBbcEqGf/PXw1EjAZ+q2/bEBg3DvurK3Q=="
     },
+    "node_modules/blueimp-file-upload": {
+      "version": "9.12.5",
+      "resolved": "https://registry.npmjs.org/blueimp-file-upload/-/blueimp-file-upload-9.12.5.tgz",
+      "integrity": "sha512-hWHp6GDoNVBV6zmU5voMqFBGAFS7KZ6I1rZhRqIPsj+2XruxPHz7M24Hvl3lcEQizY4mZo0VedIqMT7UEWT5Dg=="
+    },
     "node_modules/entities": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/entities/-/entities-2.1.0.tgz",