[jdbc-v2] Incorrect timezone transformation when reading from ClickHouse #2496

Description

I've been using the JDBC driver 0.7.2 for quite a while and now decided to update to 0.9.0.
Unfortunately I found that the update to the new driver broke the reading of timestamps. To be exact: Timestamps are read with an incorrect "time" value as the timezone is incorrectly translated to the clients timezone.
This currently blocks me from using any version beyond 0.7.2 (and without applying any workarounds).

Steps to reproduce

1. Have a ClickHouse server running with UTC (default timezone settings of the driver are used)
2. Use a client that runs on a different timezone (e.g. GMT+01:00)
3. Write a timestamp to ClickHouse (e.g. "2025-07-01T01:00:00+01:00")
4. Check the timestamp inside the ClickHouse DB (which is correctly set to "2025-07-01T00:00:00Z")
5. Read the timestamp with the same setup
6. Find that the timestamp is now different (e.g. for this example "2025-07-01T00:00:00+01:00")

Expected Behaviour

Different timezones should not cause a different timestamp to be returned from the DB.

Code Example

I'm using Spring Data repositories to access my data, so the example for me is pretty minimal, which is essentially:

var writtenEntity = clickHouseRepository.save(entityToWrite)
val readEntity = clickHouseRepository.findById(writtenEntity.id)

The timestamps within those entities are now different and it used to work with 0.7.2
No other changes were made besides updating to the new driver version.

Potential location of the issue

I think the issue is at:

Beside this I also found that the getTimestamp implementation of the ResultSet to be wrong:

Configuration

Client Configuration

Nothing specific - defaults were used

Environment

• JDBC version: 0.9.0
• Language version: Java 21
• OS: Linux

ClickHouse Server

• ClickHouse Server version: 25.6
• ClickHouse Server non-default settings, if any: N/A
• CREATE TABLE statements for tables involved:

CREATE TABLE IF NOT EXISTS my_db.my_table
(
    id             UUID,
    other_id       Int32,
    payload        String,
    timestamp      DateTime64(3, 'UTC')
    ) ENGINE = ReplacingMergeTree()
ORDER BY other_id;