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/HomePage.tsx

@@ -84,6 +84,8 @@ function WaveHome() {
     staleTime: Infinity,
   });
 
+  const showActivities = user.ui_prefs.home_activities !== false;
+  const showMoods = user.ui_prefs.home_moods !== false;
   const waveOn = st.wave !== null;
   const playing = waveOn && st.playing;
   const track = waveOn ? st.track : null;
@@ -133,22 +135,26 @@ function WaveHome() {
       {st.error === 'wave.empty' && <p className={s.note}>{t('wave.empty')}</p>}
       <FormError>{error ? errorText(error) : null}</FormError>
 
-      {options.data && (
+      {options.data && (showActivities || showMoods) && (
         <div className={s.picker}>
-          <Chips
-            title={t('wave.activity_label')}
-            options={options.data.activities}
-            value={activity}
-            label={(k) => tr(`wave.activities.${k}`)}
-            onPick={(k) => choose('activity', k)}
-          />
-          <Chips
-            title={t('wave.mood_label')}
-            options={options.data.moods}
-            value={mood}
-            label={(k) => tr(`wave.moods.${k}`)}
-            onPick={(k) => choose('mood', k)}
-          />
+          {showActivities && (
+            <Chips
+              title={t('wave.activity_label')}
+              options={options.data.activities}
+              value={activity}
+              label={(k) => tr(`wave.activities.${k}`)}
+              onPick={(k) => choose('activity', k)}
+            />
+          )}
+          {showMoods && (
+            <Chips
+              title={t('wave.mood_label')}
+              options={options.data.moods}
+              value={mood}
+              label={(k) => tr(`wave.moods.${k}`)}
+              onPick={(k) => choose('mood', k)}
+            />
+          )}
         </div>
       )}
     </div>