fix(mail): drop contacts from the EAS bundle — Stalwart 404s empty addressbook homes

BackendCombined login is all-or-nothing, and Stalwart returns 404 for
/dav/card/<account>/ when the account's default address book was never
created (it doesn't auto-create on the gateway's PROPFIND the way the
calendar home worked) — so CardDAV killed every otherwise-successful
EAS login. Exchange accounts now bundle mail + calendar; contacts stay
on the Apple-profile CardDAV path. Re-enable BackendCardDAV once
platform-api provisions a default address book at mailbox creation.

Copy/docs aligned: portal hint, SERVICES.md, website FAQ (da+en).

services/zpush/config/combined.config.php

@@ -1,10 +1,16 @@
 <?php
 // dezky replacement for Z-Push's backend/combined/config.php (applied at
-// image build, see Dockerfile). One EAS account fans out to three Stalwart
-// protocols: mail over IMAP, calendar/tasks over CalDAV, contacts over
-// CardDAV. Login succeeds only if every backend authenticates — they all
-// hit the same Stalwart account with the same credentials, so that's one
-// effective check.
+// image build, see Dockerfile). One EAS account fans out to Stalwart over
+// IMAP (mail) and CalDAV (calendar/tasks). Login succeeds only if every
+// backend authenticates — they all hit the same Stalwart account with the
+// same credentials, so that's one effective check.
+//
+// CardDAV (contacts) is deliberately NOT in the bundle yet: the combined
+// login is all-or-nothing, and Stalwart 404s the addressbook home of any
+// account whose default address book was never created — which killed every
+// EAS login on first deploy. Re-add 'd' => BackendCardDAV once platform-api
+// provisions a default address book at mailbox creation. Apple devices get
+// contacts via the .mobileconfig CardDAV payload meanwhile.
 
 class BackendCombinedConfig {
 
@@ -13,7 +19,6 @@ class BackendCombinedConfig {
             'backends' => array(
                 'i' => array('name' => 'BackendIMAP'),
                 'c' => array('name' => 'BackendCalDAV'),
-                'd' => array('name' => 'BackendCardDAV'),
             ),
             'delimiter' => '/',
             'folderbackend' => array(
@@ -28,10 +33,10 @@ class BackendCombinedConfig {
                 SYNC_FOLDER_TYPE_USER_APPOINTMENT => 'c',
                 SYNC_FOLDER_TYPE_TASK => 'c',
                 SYNC_FOLDER_TYPE_USER_TASK => 'c',
-                SYNC_FOLDER_TYPE_CONTACT => 'd',
-                SYNC_FOLDER_TYPE_USER_CONTACT => 'd',
-                // No notes/journal store in Stalwart — let mail own the rest
-                // so folder creation never lands on a DAV backend by surprise.
+                // No contacts/notes/journal on EAS for now — let mail own
+                // them so folder creation never lands somewhere surprising.
+                SYNC_FOLDER_TYPE_CONTACT => 'i',
+                SYNC_FOLDER_TYPE_USER_CONTACT => 'i',
                 SYNC_FOLDER_TYPE_NOTE => 'i',
                 SYNC_FOLDER_TYPE_USER_NOTE => 'i',
                 SYNC_FOLDER_TYPE_JOURNAL => 'i',