Keep a missing /assets file a real 404 in the SPA fallback

A stale browser tab referencing a bundle removed by a later deploy
should get a clean 404, not HTML served where JS was expected.

src/main/scala/server/Server.scala

@@ -211,6 +211,11 @@ class Server(postgresService: PostgresService, dataService: DataService, fetch:
   // real, observed on /faktiska and /udens-temperatura in production.
   private val assets = staticcontent.fileService[IO](FileService.Config("./web/dist"))
   private val spaFallback = HttpRoutes.of[IO] {
+    // A missing file under /assets (the only place Vite emits hashed build
+    // output) should stay a real 404, not silently serve HTML — otherwise a
+    // stale tab referencing a since-removed bundle after a future deploy
+    // would get a confusing "unexpected token" JS parse error instead.
+    case GET -> Root / "assets" / _ => NotFound()
     case req @ GET -> _ =>
       StaticFile.fromPath(Path("./web/dist/index.html"), Some(req)).getOrElseF(NotFound())
   }