feat: localization (#196)

* Started adding locale translations :)

* Added some more translations

* Working on translating even more pages

* More translations

* Added test default locale retrieval

* replace `intl.formatMessage` with custom `t` hook

* add more translations

* improve title syntax

* add more translations

* translate admin config page

* translated error messages

* add language selecter

* minor fixes

* improve language handling

* add upcoming languages

* add `crowdin.yml`

* run formatter

---------

Co-authored-by: Steve Tautonico <stautonico@gmail.com>

frontend/src/components/admin/users/ManageUserTable.tsx

@@ -3,6 +3,7 @@ import { useModals } from "@mantine/modals";
 import { TbCheck, TbEdit, TbTrash } from "react-icons/tb";
 import User from "../../../types/user.type";
 import showUpdateUserModal from "./showUpdateUserModal";
+import { FormattedMessage, useIntl } from "react-intl";
 
 const ManageUserTable = ({
   users,
@@ -22,9 +23,15 @@ const ManageUserTable = ({
       <Table verticalSpacing="sm">
         <thead>
           <tr>
-            <th>Username</th>
-            <th>Email</th>
-            <th>Admin</th>
+            <th>
+              <FormattedMessage id="admin.users.table.username" />
+            </th>
+            <th>
+              <FormattedMessage id="admin.users.table.email" />
+            </th>
+            <th>
+              <FormattedMessage id="admin.users.table.admin" />
+            </th>
             <th></th>
           </tr>
         </thead>