fix(posture): page size selector now applies correctly

const → let and pageSizeChange handler was discarding e.detail.size.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/components/DevicePosture.svelte

@@ -8,7 +8,7 @@
   let totalElements = 0;
   let totalPages = 0;
   let currentPage = 0;
-  const pageSize = 25;
+  let pageSize = 25;
 
   let loading = true;
 
@@ -248,7 +248,7 @@
             <Pagination
               page={currentPage} {totalPages} {totalElements} size={pageSize}
               on:pageChange={e => { currentPage = e.detail.page; load(currentPage); }}
-              on:pageSizeChange={e => { currentPage = 0; load(0); }}
+              on:pageSizeChange={e => { pageSize = e.detail.size; currentPage = 0; load(0); }}
             />
 
             <div class="table-container">