Consistent Add/Invite buttons in projects and orgs (#1078)

The "Invite" checkbox for adding org members wasn't changing the text of
the button the way the project dialog was. Now they're consistent.

frontend/src/lib/i18n/locales/en.json

@@ -264,8 +264,7 @@ the [Linguistics Institute at Payap University](https://li.payap.ac.th/) in Chia
       "__comment_modal_title": "Should become 'Add or invite a Member ...' once email invitations implemented for orgs",
       "submit_button": "Add Member",
       "empty_user_field": "Please enter an email address or login",
-      "submit_button_email": "Add Member",
-      "__comment_submit_button_email": "Should become 'Add or invite Member' once email invitations implemented for orgs",
+      "submit_button_email": "Add/Invite Member",
       "org_not_found": "Organization not found. Please refresh the page.",
       "username_not_found": "No user was found with this login",
       "user_must_be_verified": "User needs a verified email address",

frontend/src/routes/(authenticated)/org/[org_id]/AddOrgMemberModal.svelte

@@ -91,7 +91,7 @@
     />
   </svelte:fragment>
   <span slot="submitText">
-    {#if $form.usernameOrEmail.includes('@')}
+    {#if $form.canInvite && $form.usernameOrEmail.includes('@')}
       {$t('org_page.add_user.submit_button_email')}
     {:else}
       {$t('org_page.add_user.submit_button')}

frontend/src/routes/(authenticated)/project/[project_code]/AddProjectMember.svelte

@@ -98,7 +98,7 @@
     />
   </svelte:fragment>
   <span slot="submitText">
-    {#if $form.canInvite}
+    {#if $form.canInvite && $form.usernameOrEmail.includes('@')}
       {$t('project_page.add_user.submit_button_invite')}
     {:else}
       {$t('project_page.add_user.submit_button')}