fix(dashboards): guard convex query and refine empty state CTA

src/components/dashboards/dashboard-builder.tsx

@@ -462,10 +462,11 @@ export function DashboardBuilder({ dashboardId, editable = true, mode = "edit" }
   const tenantId = session?.user.tenantId ?? DEFAULT_TENANT_ID
   const viewerId = convexUserId as Id<"users"> | null
   const canEdit = editable && Boolean(viewerId) && isStaff
+  const hasDashboardId = typeof dashboardId === "string" && dashboardId.length > 0
 
   const detail = useQuery(
     api.dashboards.get,
-    viewerId
+    viewerId && hasDashboardId
       ? ({
           tenantId,
           viewerId: viewerId as Id<"users">,

src/components/dashboards/dashboard-list.tsx

@@ -199,6 +199,10 @@ export function DashboardListView() {
 
   const activeDashboards = dashboards.filter((dashboard) => !dashboard.isArchived)
 
+  const renderCreateButton = () => (
+    <CreateDashboardDialog onCreate={handleCreate} isLoading={isCreating} />
+  )
+
   return (
     <div className="space-y-6">
       <div className="flex flex-wrap items-center justify-between gap-3">
@@ -208,7 +212,7 @@ export function DashboardListView() {
             Combine KPIs, gráficos, tabelas e texto em painéis dinâmicos com filtros globais.
           </p>
         </div>
-        <CreateDashboardDialog onCreate={handleCreate} isLoading={isCreating} />
+        {activeDashboards.length > 0 ? renderCreateButton() : null}
       </div>
 
       {activeDashboards.length === 0 ? (
@@ -223,7 +227,7 @@ export function DashboardListView() {
                 Monte painéis por cliente, fila ou operação e compartilhe com a equipe.
               </CardDescription>
             </div>
-            <CreateDashboardDialog onCreate={handleCreate} isLoading={isCreating} />
+            {renderCreateButton()}
           </CardHeader>
           <CardContent className="space-y-2 text-sm text-muted-foreground">
             <p>• Arraste e redimensione widgets livremente no canvas.</p>