feat: offer items drag-and-drop reordering + fix scope template insertion

1. Item reordering: replaced placeholder with @dnd-kit drag-and-drop.
   Each item row has a drag handle for reordering via vertical drag.
   Uses SortableContext with verticalListSortingStrategy.

2. Scope template insertion: fixed template loading to use already-fetched
   data instead of re-fetching from non-existent endpoint. Templates with
   sections are now stored fully and inserted directly on selection.
   Also copies template description to scope_description.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

package.json

@@ -24,6 +24,10 @@
   "license": "ISC",
   "type": "commonjs",
   "dependencies": {
+    "@dnd-kit/core": "^6.3.1",
+    "@dnd-kit/modifiers": "^9.0.0",
+    "@dnd-kit/sortable": "^10.0.0",
+    "@dnd-kit/utilities": "^3.2.2",
     "@fastify/cookie": "^11.0.2",
     "@fastify/cors": "^11.2.0",
     "@fastify/multipart": "^9.4.0",