feat(web): settings to keep the search open and hide home pickers; collapsible menu sections

- appearance settings get "collapse search" (off keeps the field always open)
  and separate switches for the activity and mood pickers on the home page;
  stored in ui_prefs (search_collapse, home_activities, home_moods)
- Collection and Admin headers in the sidebar fold their items; the state is
  remembered in the browser, a folded Admin shows the review queue badge;
  icon-only and phone layouts always show every item

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/pages/SettingsPage.tsx

@@ -139,6 +139,42 @@ function AppearanceSection() {
           ]}
         />
       </div>
+      <div className={s.settingRow}>
+        <span>{t('settings.search_collapse')}</span>
+        <Segmented<'on' | 'off'>
+          label={t('settings.search_collapse')}
+          value={user.ui_prefs.search_collapse === false ? 'off' : 'on'}
+          onChange={(v) => void setPrefs({ search_collapse: v === 'on' })}
+          options={[
+            { value: 'on', label: t('settings.on') },
+            { value: 'off', label: t('settings.off') },
+          ]}
+        />
+      </div>
+      <div className={s.settingRow}>
+        <span>{t('settings.home_activities')}</span>
+        <Segmented<'on' | 'off'>
+          label={t('settings.home_activities')}
+          value={user.ui_prefs.home_activities === false ? 'off' : 'on'}
+          onChange={(v) => void setPrefs({ home_activities: v === 'on' })}
+          options={[
+            { value: 'on', label: t('settings.on') },
+            { value: 'off', label: t('settings.off') },
+          ]}
+        />
+      </div>
+      <div className={s.settingRow}>
+        <span>{t('settings.home_moods')}</span>
+        <Segmented<'on' | 'off'>
+          label={t('settings.home_moods')}
+          value={user.ui_prefs.home_moods === false ? 'off' : 'on'}
+          onChange={(v) => void setPrefs({ home_moods: v === 'on' })}
+          options={[
+            { value: 'on', label: t('settings.on') },
+            { value: 'off', label: t('settings.off') },
+          ]}
+        />
+      </div>
       <div className={s.settingRow}>
         <span>{t('settings.ambient')}</span>
         <Segmented<'on' | 'off'>