include code in invite form instead of getting from url

potentially solves #34?

html/form-base.html

@@ -4,6 +4,7 @@
     window.validationStrings = JSON.parse({{ .lang.validationStrings }});
     window.invalidPassword = "{{ .lang.reEnterPasswordInvalid }}";
     window.URLBase = "{{ .urlBase }}";
+    window.code = "{{ .code }}";
 </script>
 <script src="js/form.js" type="module"></script>
 {{ end }}

ts/form.ts

@@ -5,6 +5,7 @@ interface formWindow extends Window {
     validationStrings: pwValStrings;
     invalidPassword: string;
     modal: Modal;
+    code: string;
 }
 
 interface pwValString {
@@ -103,7 +104,7 @@ const create = (event: SubmitEvent) => {
     event.preventDefault();
     toggleLoader(submitSpan);
     let send: sendDTO = {
-        code: window.location.href.split('/').pop(),
+        code: window.code,
         username: usernameField.value,
         email: emailField.value,
         password: passwordField.value

views.go

@@ -56,6 +56,7 @@ func (app *appContext) InviteProxy(gc *gin.Context) {
 			"email":          email,
 			"username":       !app.config.Section("email").Key("no_username").MustBool(false),
 			"lang":           app.storage.lang.Form[lang]["strings"],
+			"code":           code,
 		})
 	} else {
 		gcHTML(gc, 404, "invalidCode.html", gin.H{