Adding pervasive column sorting

app/templates/admin/_augmented_parts_table.html

@@ -10,6 +10,8 @@
         hx-target="#augmented-parts-table-card"
         hx-trigger="input delay:300ms, change"
         hx-swap="outerHTML">
+    <input type="hidden" name="sort" value="{{ sort }}">
+    <input type="hidden" name="dir" value="{{ dir }}">
     <input type="text" name="description" placeholder="Filter by description…" value="{{ filter_description or '' }}">
     <select name="colour_id">
       <option value="">All colours</option>