feat(mui): consistent staggered page entrance across all 43 route pages

Adopt the PageEnter wrapper as every page's outermost render element and remove the ad-hoc per-page entrance motion.div wrappers. Every page now enters the same way — all top-level sections rise+fade in, staggered — so nothing appears instantly and the motion is identical app-wide. Presentation-only: no data/logic/hooks/invalidate/permissions touched. Embedded sub-tabs (CompanySettings, ReceivedInvoices), Login (auth shell) and the dev UiKit are intentionally excluded. Gates: tsc -b --noEmit=0, build=0, vitest 152/152.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/pages/OffersCustomers.tsx

@@ -1,6 +1,5 @@
 import { useState, useCallback, useRef } from "react";
 import { useQuery } from "@tanstack/react-query";
-import { motion } from "framer-motion";
 import Box from "@mui/material/Box";
 import Typography from "@mui/material/Typography";
 import IconButton from "@mui/material/IconButton";
@@ -24,6 +23,7 @@ import {
   CheckboxField,
   StatusChip,
   PageHeader,
+  PageEnter,
   FilterBar,
   EmptyState,
   LoadingState,
@@ -468,24 +468,18 @@ export default function OffersCustomers() {
   ];
 
   return (
-    <Box>
-      <motion.div
-        initial={{ opacity: 0, y: 12 }}
-        animate={{ opacity: 1, y: 0 }}
-        transition={{ duration: 0.25 }}
-      >
-        <PageHeader
-          title="Zákazníci"
-          subtitle="Správa zákazníků pro nabídky"
-          actions={
-            hasPermission("customers.create") ? (
-              <Button startIcon={PlusIcon} onClick={openCreateModal}>
-                Přidat zákazníka
-              </Button>
-            ) : undefined
-          }
-        />
-      </motion.div>
+    <PageEnter>
+      <PageHeader
+        title="Zákazníci"
+        subtitle="Správa zákazníků pro nabídky"
+        actions={
+          hasPermission("customers.create") ? (
+            <Button startIcon={PlusIcon} onClick={openCreateModal}>
+              Přidat zákazníka
+            </Button>
+          ) : undefined
+        }
+      />
 
       <FilterBar>
         <Box sx={{ flex: "1 1 320px" }}>
@@ -816,6 +810,6 @@ export default function OffersCustomers() {
         confirmVariant="danger"
         loading={deleting}
       />
-    </Box>
+    </PageEnter>
   );
 }