Feature/show backup restore progress (#431)

* Extract "Progress" component

* Show backup restore progress

src/components/util/Progress.tsx

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+import { Box } from '@mui/material';
+import CircularProgress from '@mui/material/CircularProgress';
+import Typography from '@mui/material/Typography';
+
+export const Progress = ({ progress }: { progress: number }) => (
+    <Box sx={{ display: 'grid', placeItems: 'center', position: 'relative' }}>
+        <CircularProgress variant="determinate" value={progress} />
+        <Box sx={{ position: 'absolute' }}>
+            <Typography fontSize="0.8rem">{`${Math.round(progress)}%`}</Typography>
+        </Box>
+    </Box>
+);