feat(HAI-002): update Express server to serve Vite build output

packages/dashboard/src/server.ts

@@ -0,0 +1,28 @@
+import express from "express";
+import { join, dirname } from "node:path";
+import { fileURLToPath } from "node:url";
+import type { TaskStore } from "@hai/core";
+import { createApiRoutes } from "./routes.js";
+import { createSSE } from "./sse.js";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+export function createServer(store: TaskStore) {
+  const app = express();
+
+  app.use(express.json());
+  app.use(express.static(join(__dirname, "..", "client")));
+
+  // SSE endpoint
+  app.get("/api/events", createSSE(store));
+
+  // REST API
+  app.use("/api", createApiRoutes(store));
+
+  // SPA fallback
+  app.get("/{*splat}", (_req, res) => {
+    res.sendFile(join(__dirname, "..", "client", "index.html"));
+  });
+
+  return app;
+}