fix: bundle UI dist into server package for npm publishing

The server's static-ui mode resolves the UI dist path relative to its
own directory. In the monorepo it finds ../../ui/dist, but when published
to npm the UI package isn't available.

- server/src/app.ts: try ../ui-dist (published) then ../../ui/dist (dev),
  gracefully degrade to API-only if neither exists
- server/package.json: include ui-dist/ in published files
- scripts/release.sh: build UI and copy dist to server/ui-dist before
  publishing, clean up in restore step

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/package.json

@@ -17,7 +17,8 @@
     "types": "./dist/index.d.ts"
   },
   "files": [
-    "dist"
+    "dist",
+    "ui-dist"
   ],
   "scripts": {
     "dev": "tsx src/index.ts",

server/src/app.ts

@@ -124,12 +124,20 @@ export async function createApp(
 
   const __dirname = path.dirname(fileURLToPath(import.meta.url));
   if (opts.uiMode === "static") {
-    // Serve built UI from ui/dist in production.
-    const uiDist = path.resolve(__dirname, "../../ui/dist");
-    app.use(express.static(uiDist));
-    app.get(/.*/, (_req, res) => {
-      res.sendFile(path.join(uiDist, "index.html"));
-    });
+    // Try published location first (server/ui-dist/), then monorepo dev location (../../ui/dist)
+    const candidates = [
+      path.resolve(__dirname, "../ui-dist"),
+      path.resolve(__dirname, "../../ui/dist"),
+    ];
+    const uiDist = candidates.find((p) => fs.existsSync(path.join(p, "index.html")));
+    if (uiDist) {
+      app.use(express.static(uiDist));
+      app.get(/.*/, (_req, res) => {
+        res.sendFile(path.join(uiDist, "index.html"));
+      });
+    } else {
+      console.warn("[paperclip] UI dist not found; running in API-only mode");
+    }
   }
 
   if (opts.uiMode === "vite-dev") {