feat(applications): drag-to-reorder on the public site

Editors can now control the order applications appear in, the same way they
already reorder Hero slides.

- Application gains an `order Int @default(0)` column (additive migration
  20260605120000_add_application_order, IF NOT EXISTS, safe for deploy) plus
  an (isActive, order) index.
- New reorderApplications(orderedSlugs) server action — single $transaction
  renumbering, mirrors reorderHeroSlides.
- HQ applications panel: rows are now draggable by a grip handle (HTML5 DnD,
  optimistic local reorder, persisted on drop, toast feedback).
- All public-facing queries now order by [order asc, createdAt asc]: home
  ApplicationsDashboard + GlobalOperations, the footer apps list, and the
  HQ list itself. Existing rows default to 0 so current order is preserved
  until the editor drags something.

Verified: production build compiles, TypeScript clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/hq-command/dashboard/applications/actions.ts

@@ -18,7 +18,7 @@ export async function getApplications() {
   noStore(); 
   try {
     const apps = await prisma.application.findMany({
-      orderBy: { createdAt: "asc" }
+      orderBy: [{ order: "asc" }, { createdAt: "asc" }]
     });
     return { success: true, apps };
   } catch (error) {
@@ -161,6 +161,24 @@ export async function deleteApplication(slug: string) {
   }
 }
 
+// 6b. REORDENAR APLICACIONES (drag-to-reorder, mismo patrón que HeroSlide)
+// Recibe la lista de slugs en el nuevo orden y renumera el campo `order`
+// en una sola transacción atómica.
+export async function reorderApplications(orderedSlugs: string[]) {
+  try {
+    await prisma.$transaction(
+      orderedSlugs.map((slug, idx) =>
+        prisma.application.update({ where: { slug }, data: { order: idx } })
+      )
+    );
+    revalidatePath("/hq-command/dashboard/applications");
+    revalidatePath("/[locale]", "layout");
+    return { success: true };
+  } catch (e) {
+    return { error: "Failed to reorder applications." };
+  }
+}
+
 // 7. LA SEMILLA: AUTO-POBLAR LA BASE DE DATOS (Intacto)
 export async function seedInitialApplications() {
   // ... Tu código actual de la semilla se queda exactamente igual ...