Feat(Gotenberg): Opt-in alternative pdf generation for modern CSS (#184)

* WIP(gotenberg): add pdf generation abstraction and UI

* feat(pdf): settings validate(clien+server) & save

* fix(gotenberg): Use correct default papersize
chore(gotengberg): Remove unused GOTENBERG_MARGINS env from .env

* style(gotenberg): fix linter/styling issues

* fix(pdf): use pdf config policy

* fix: revert accidental capitalization in mail config vue

* Update composer, remove whitespace typo

* Fix small typos

* fix cookie/env issue

* Add gotenberg to .dev, move admin menu item up

app/Policies/SettingsPolicy.php

@@ -46,6 +46,15 @@ class SettingsPolicy
         return false;
     }
 
+    public function managePDFConfig(User $user)
+    {
+        if ($user->isOwner()) {
+            return true;
+        }
+
+        return false;
+    }
+
     public function manageSettings(User $user)
     {
         if ($user->isOwner()) {