Improve "Load more" error handling in feeds (#379)

* Add explicit load-more error handling to posts feed

* Add explicit load-more error handling to notifications feed

* Properly set hasMore to false after an error

src/view/com/util/LoadMoreRetryBtn.tsx

@@ -0,0 +1,44 @@
+import React from 'react'
+import {StyleSheet} from 'react-native'
+import {
+  FontAwesomeIcon,
+  FontAwesomeIconStyle,
+} from '@fortawesome/react-native-fontawesome'
+import {Button} from './forms/Button'
+import {Text} from './text/Text'
+import {usePalette} from 'lib/hooks/usePalette'
+
+export function LoadMoreRetryBtn({
+  label,
+  onPress,
+}: {
+  label: string
+  onPress: () => void
+}) {
+  const pal = usePalette('default')
+  return (
+    <Button type="default-light" onPress={onPress} style={styles.loadMoreRetry}>
+      <FontAwesomeIcon
+        icon="arrow-rotate-left"
+        style={pal.textLight as FontAwesomeIconStyle}
+        size={18}
+      />
+      <Text style={[pal.textLight, styles.label]}>{label}</Text>
+    </Button>
+  )
+}
+
+const styles = StyleSheet.create({
+  loadMoreRetry: {
+    flexDirection: 'row',
+    gap: 14,
+    alignItems: 'center',
+    borderRadius: 0,
+    marginTop: 1,
+    paddingVertical: 12,
+    paddingHorizontal: 20,
+  },
+  label: {
+    flex: 1,
+  },
+})