Client does not check if it is able to connect to qdrant

[Sebi2020]

The qdrant client library currently does not verify if it is able to connect to qdrant server. If it is able to connect is only detectable after issuing the first api call.

For example:

QdrantConfig::from_url("http://localhost:6334")
    .connect_timeout(Duration::from_secs(4))
    .build()
    .map_err(|e| Error::new(ErrorKind::Other, e))?;

succeeds immediately. Even if there is no server running at http://localhost:6334. This makes it difficult to observe connection errors. Tested on MacOS 26.1.