fix(06.2): shared badge and recipient handle missing in FileManagerView

- shares.py grant_share: include recipient_handle in response so ShareModal shows the name immediately without reload
- FileManagerView: add Shared pill badge next to document name (badge only existed in DocumentCard, not the main file manager view)
- FileManagerView ShareModal: wire @unshared to clear is_shared flag when last recipient is removed

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

backend/api/shares.py

@@ -152,6 +152,7 @@ async def grant_share(
         "document_id": str(share.document_id),
         "owner_id": str(share.owner_id),
         "recipient_id": str(share.recipient_id),
+        "recipient_handle": recipient.handle,
         "permission": share.permission,
         "created_at": share.created_at.isoformat() if share.created_at else None,
     }

frontend/src/views/FileManagerView.vue

@@ -152,7 +152,10 @@
 
           <!-- Name + topics -->
           <div class="min-w-0">
-            <p class="text-sm font-medium text-gray-900 truncate">{{ doc.original_name }}</p>
+            <div class="flex items-center gap-2">
+              <p class="text-sm font-medium text-gray-900 truncate">{{ doc.original_name }}</p>
+              <span v-if="doc.is_shared" class="shrink-0 bg-indigo-50 text-indigo-600 text-xs font-medium px-2 py-0.5 rounded-full">Shared</span>
+            </div>
             <div v-if="doc.topics?.length" class="flex items-center gap-1 mt-0.5 flex-wrap">
               <TopicBadge v-for="t in doc.topics.slice(0, 3)" :key="t" :name="t" :color="topicColor(t)" />
             </div>
@@ -245,6 +248,7 @@
       v-if="shareDoc"
       :doc="shareDoc"
       @close="shareDoc = null"
+      @unshared="(id) => { const d = docsStore.documents.find(x => x.id === id); if (d) d.is_shared = false }"
     />
   </div>
 </template>