feat(plan): wire plan routes into the server

src/server.ts

@@ -34,6 +34,7 @@ import offersPdfRoutes from "./routes/admin/offers-pdf";
 import ordersPdfRoutes from "./routes/admin/orders-pdf";
 import projectFilesRoutes from "./routes/admin/project-files";
 import warehouseRoutes from "./routes/admin/warehouse";
+import planRoutes from "./routes/admin/plan";
 
 const app = Fastify({
   logger: {
@@ -150,6 +151,7 @@ async function start() {
     prefix: "/api/admin/project-files",
   });
   await app.register(warehouseRoutes, { prefix: "/api/admin/warehouse" });
+  await app.register(planRoutes, { prefix: "/api/admin/plan" });
 
   // --- Frontend: Vite dev middleware (dev only) ---
   if (!config.isProduction) {