implement new invitation system

* fix comments on the frontend
* move jwt token service to its own module
* other fixes and updates

apps/server/src/integrations/transactional/emails/invitation-email.tsx

@@ -0,0 +1,37 @@
+import { Section, Text, Button } from '@react-email/components';
+import * as React from 'react';
+import { button, content, paragraph } from '../css/styles';
+import { MailBody } from '../partials/partials';
+
+interface Props {
+  inviteLink: string;
+}
+
+export const InvitationEmail = ({ inviteLink }: Props) => {
+  return (
+    <MailBody>
+      <Section style={content}>
+        <Text style={paragraph}>Hi there,</Text>
+        <Text style={paragraph}>You have been invited to Docmost.</Text>
+        <Text style={paragraph}>
+          Please click the button below to accept this invitation.
+        </Text>
+      </Section>
+      <Section
+        style={{
+          display: 'flex',
+          justifyContent: 'center',
+          alignItems: 'center',
+          paddingLeft: '15px',
+          paddingBottom: '15px',
+        }}
+      >
+        <Button href={inviteLink} style={button}>
+          Accept Invite
+        </Button>
+      </Section>
+    </MailBody>
+  );
+};
+
+export default InvitationEmail;