PWI improvements (#3489)

* Enable home and feeds on the PWI

* Add global SigninDialog to drive useRequireAuth()

* Tweak desktop styles

* Make the logo in leftnav PWI a clickable home link

* Add label

* Improve dialog on web

* Fix query key

* Go to home after signout from settings screen

* Filter out feeds from the discover listing for logged out users which are known to break without auth

* Update profile header follow/subscribe to give signin prompt

* Show profile feeds tabs on pwi

* Add language selector to account creation footer and pwi left nav desktop

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Co-authored-by: dan <dan.abramov@gmail.com>

src/components/AppLanguageDropdown.web.tsx

@@ -0,0 +1,62 @@
+import React from 'react'
+import {View} from 'react-native'
+
+import {sanitizeAppLanguageSetting} from '#/locale/helpers'
+import {APP_LANGUAGES} from '#/locale/languages'
+import {useLanguagePrefs, useLanguagePrefsApi} from '#/state/preferences'
+import {atoms as a, useTheme} from '#/alf'
+import {ChevronBottom_Stroke2_Corner0_Rounded as ChevronDown} from '#/components/icons/Chevron'
+import {Text} from '#/components/Typography'
+
+export function AppLanguageDropdown() {
+  const t = useTheme()
+
+  const langPrefs = useLanguagePrefs()
+  const setLangPrefs = useLanguagePrefsApi()
+
+  const sanitizedLang = sanitizeAppLanguageSetting(langPrefs.appLanguage)
+
+  const onChangeAppLanguage = React.useCallback(
+    (ev: React.ChangeEvent<HTMLSelectElement>) => {
+      const value = ev.target.value
+
+      if (!value) return
+      if (sanitizedLang !== value) {
+        setLangPrefs.setAppLanguage(sanitizeAppLanguageSetting(value))
+      }
+    },
+    [sanitizedLang, setLangPrefs],
+  )
+
+  return (
+    <View style={[a.flex_row, a.gap_sm, a.align_center, a.flex_shrink]}>
+      <Text aria-hidden={true} style={t.atoms.text_contrast_medium}>
+        {APP_LANGUAGES.find(l => l.code2 === sanitizedLang)?.name}
+      </Text>
+      <ChevronDown fill={t.atoms.text.color} size="xs" style={a.flex_shrink} />
+
+      <select
+        value={sanitizedLang}
+        onChange={onChangeAppLanguage}
+        style={{
+          cursor: 'pointer',
+          MozAppearance: 'none',
+          WebkitAppearance: 'none',
+          appearance: 'none',
+          position: 'absolute',
+          inset: 0,
+          width: '100%',
+          color: 'transparent',
+          background: 'transparent',
+          border: 0,
+          padding: 0,
+        }}>
+        {APP_LANGUAGES.filter(l => Boolean(l.code2)).map(l => (
+          <option key={l.code2} value={l.code2}>
+            {l.name}
+          </option>
+        ))}
+      </select>
+    </View>
+  )
+}