admin: streamline item modal actions

backend/src/routes/admin.js

@@ -394,6 +394,10 @@ router.get('/custom-items', requireAdmin, async (req, res) => {
     q: z.string().trim().max(120).optional().default(''),
     page: z.coerce.number().int().min(1).optional().default(1),
     limit: z.coerce.number().int().min(1).max(200).optional().default(50),
+    collapseShared: z
+      .union([z.string(), z.boolean(), z.number()])
+      .optional()
+      .transform((value) => value === true || value === 1 || value === '1' || value === 'true'),
     filter: z
       .enum(['library', 'all', 'user', 'template', 'asset', 'thumbnail', 'avatar', 'unused', 'unused-user', 'replaced-user', 'unused-admin'])
       .optional()
@@ -407,6 +411,7 @@ router.get('/custom-items', requireAdmin, async (req, res) => {
     page: parsed.data.page,
     limit: parsed.data.limit,
     filterMode: parsed.data.filter,
+    collapseShared: parsed.data.collapseShared,
   })
   res.json(result)
 })
@@ -862,6 +867,27 @@ router.post('/custom-items/:itemId/promote', requireAdmin, async (req, res) => {
   res.json({ item })
 })
 
+router.post('/custom-items/:itemId/unlink-template', requireAdmin, async (req, res) => {
+  const schema = z.object({
+    topicId: z.string().trim().min(1),
+  })
+  const parsed = schema.safeParse(req.body)
+  if (!parsed.success) return res.status(400).json({ error: 'bad_request' })
+
+  const template = await findTopicById(parsed.data.topicId)
+  if (!template) return res.status(404).json({ error: 'topic_not_found' })
+
+  const sourceItem = await findLibraryItemForReplacement(req.params.itemId)
+  if (!sourceItem?.src) return res.status(404).json({ error: 'not_found' })
+
+  const templateItems = await listTopicItems(template.id)
+  const matchedItems = templateItems.filter((item) => item?.src === sourceItem.src)
+  if (!matchedItems.length) return res.status(404).json({ error: 'linked_template_item_not_found' })
+
+  await Promise.all(matchedItems.map((item) => deleteTopicItem(item.id)))
+  res.json({ ok: true, deletedCount: matchedItems.length, topicId: template.id, src: sourceItem.src })
+})
+
 router.post('/custom-items/:itemId/replace', requireAdmin, async (req, res) => {
   const schema = z.object({
     targetItemId: z.string().trim().min(1),