fix: double config path, stale service worker, empty op-name log

- main.go: DOCKER_PATH=/config + /config.json (was /config/config.json)
- vite.config.ts: skipWaiting+clientsClaim forces new SW immediately;
  navigateFallback: null prevents SW from serving stale index.html;
  globPatterns excludes HTML so navigation always hits the network
- server.go: gqlOpName handles shorthand { field } syntax

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

backend/cmd/server/main.go

@@ -39,8 +39,14 @@ func main() {
 }
 
 func configPath() string {
+	// CONFIG_DIR points directly to the config directory (preferred).
+	if p := os.Getenv("CONFIG_DIR"); p != "" {
+		return p + "/config.json"
+	}
+	// DOCKER_PATH is also set to the config directory in docker-compose
+	// (the container mounts the config dir at /config, so DOCKER_PATH=/config).
 	if p := os.Getenv("DOCKER_PATH"); p != "" {
-		return p + "/config/config.json"
+		return p + "/config.json"
 	}
 	return "config.json"
 }