chore: import upstream snapshot with attribution

ui/vite.config.ts

@@ -0,0 +1,47 @@
+import { defineConfig, Plugin } from "vite";
+import react from "@vitejs/plugin-react";
+import { viteSingleFile } from "vite-plugin-singlefile";
+import { existsSync, renameSync, rmSync } from "fs";
+import { resolve } from "path";
+
+const app = process.env.APP;
+
+if (!app) {
+  throw new Error("APP environment variable must be set");
+}
+
+const outDir = resolve(__dirname, "../pkg/github/ui_dist");
+
+// vite-plugin-singlefile inlines all JS/CSS into the HTML, but Vite preserves
+// the input file's relative path in the output (src/apps/<app>/index.html).
+// After the bundle is written, hoist that file to <outDir>/<app>.html and
+// remove the now-empty nested directories. Done in closeBundle (post-write)
+// because Rolldown disallows mutating the in-memory bundle in generateBundle.
+function flattenOutput(): Plugin {
+  return {
+    name: "flatten-output",
+    enforce: "post",
+    closeBundle() {
+      const nested = resolve(outDir, `src/apps/${app}/index.html`);
+      const flat = resolve(outDir, `${app}.html`);
+      if (!existsSync(nested)) {
+        throw new Error(
+          `flatten-output: expected built HTML at ${nested} for app "${app}" but it was not emitted`,
+        );
+      }
+      renameSync(nested, flat);
+      rmSync(resolve(outDir, "src"), { recursive: true, force: true });
+    },
+  };
+}
+
+export default defineConfig({
+  plugins: [react(), viteSingleFile(), flattenOutput()],
+  build: {
+    outDir,
+    emptyOutDir: false,
+    rollupOptions: {
+      input: resolve(__dirname, `src/apps/${app}/index.html`),
+    },
+  },
+});