feat: collapse/expand all — toggle icon in ArrayEditor + pricing sections

- ArrayEditor shows ChevronsUpDown toggle when collapsible with 2+ items
- Toggle appears even without label prop (fixes pricing missing icon)
- Pricing: centralized section state with toggle-all button for all 3 sections

src/app/admin/_components/ArrayEditor.tsx

@@ -2,7 +2,7 @@
 
 import { useState, useRef, useCallback, useEffect } from "react";
 import { createPortal } from "react-dom";
-import { Plus, Trash2, GripVertical, ChevronDown } from "lucide-react";
+import { Plus, Trash2, GripVertical, ChevronDown, ChevronsUpDown } from "lucide-react";
 
 interface ArrayEditorProps<T> {
   items: T[];
@@ -293,8 +293,23 @@ export function ArrayEditor<T>({
 
   return (
     <div>
-      {label && (
-        <h3 className="text-sm font-medium text-neutral-300 mb-3">{label}</h3>
+      {(label || (collapsible && items.length > 1)) && (
+        <div className="flex items-center justify-between mb-3">
+          {label ? <h3 className="text-sm font-medium text-neutral-300">{label}</h3> : <div />}
+          {collapsible && items.length > 1 && (() => {
+            const allCollapsed = collapsed.size >= items.length;
+            return (
+              <button
+                type="button"
+                onClick={() => allCollapsed ? setCollapsed(new Set()) : setCollapsed(new Set(items.map((_, i) => i)))}
+                className="rounded p-1 text-neutral-500 hover:text-white transition-colors"
+                title={allCollapsed ? "Развернуть все" : "Свернуть все"}
+              >
+                <ChevronsUpDown size={16} className={`transition-transform duration-200 ${allCollapsed ? "" : "rotate-90"}`} />
+              </button>
+            );
+          })()}
+        </div>
       )}
 
       {addPosition === "top" && (