feat: scaffold SvelteKit runtime

src/lib/server/dashboard.ts

@@ -0,0 +1,18 @@
+export type PlaceholderStatus = "ready" | "building";
+
+export interface PlaceholderDashboard {
+  title: string;
+  subtitle: string;
+  status: PlaceholderStatus;
+  message: string;
+}
+
+export function loadPlaceholderDashboard(): PlaceholderDashboard {
+  return {
+    title: "System Overview",
+    subtitle: "Dashboard runtime scaffold",
+    status: "building",
+    message:
+      "SvelteKit is running. Later issues will replace this placeholder with the validated dashboard model.",
+  };
+}