Fix share copy-link, destination-picker filters, and type-filter UX

- SharesController's fetchShares() built NextcloudShare objects through
  its own thin inline parser instead of _shareFromJson, so url/token/
  permissions/expireDate were always null - a public link share could
  never show "Copy link" in the Shares tab. Reuses _shareFromJson.
- Upload/Move/Copy's destination picker hid External storage in its
  filter sheet (showStorageScope: false) unlike Files' own controls
  row, despite the design doc already calling for full parity.
- Files' and Photos' type filter (All/Files/Folders, All/Photos/Videos)
  now render as one consistent style in both filter sheets: every icon
  always shown, label only on the selected segment
  (NooSegmentedControl's new labelOnlySelected), replacing Files' old
  checkmark list and Photos' own always-labelled track.
- Fixes Photos' type filter only visually updating after closing and
  reopening the filter sheet - it lived on PhotosView's own State, so
  Listenable.merge([photos, files]) never rebuilt the sheet when it
  changed; a StatefulBuilder now gives it that trigger.
- Replaces Settings' trailing section jump rail with per-section
  collapsible cards (NooGroupedList's new collapsible param, expanded
  by default) - one less parallel way to navigate a long screen.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

lib/widgets/settings/settings_section.dart

@@ -31,6 +31,11 @@ class SettingsSection extends StatelessWidget {
       return NooGroupedList(
         label: title,
         footer: subtitle != null ? Text(subtitle!) : null,
+        // Every mobile Settings section is individually collapsible,
+        // expanded by default - replaces the old trailing jump rail (see
+        // `account_view.dart`'s doc comment) as the way to navigate a long
+        // Settings screen quickly.
+        collapsible: true,
         children: children,
       );
     }
@@ -99,8 +104,15 @@ void showSettingsPicker(
   required List<Widget> options,
 }) {
   if (NooLayout.isDesktop(context)) {
-    showNooDialog(context, title: title, children: [Column(children: options)]);
+    showNooDialog(
+      context,
+      title: title,
+      children: [Column(children: options)],
+    );
   } else {
-    showNooSheet(context, children: [NooGroupedList(label: title, children: options)]);
+    showNooSheet(
+      context,
+      children: [NooGroupedList(label: title, children: options)],
+    );
   }
 }