Add support to propagate args to the connection and other code clean ups

[ahmedriza]

Add support for propagating Session arguments to the chdb connection. This is essential when TLS configuration is required (for example when using the remoteSecure table function).

Clean up code in SessionBuilder::build, Connection::open, remove unmaintainted dev dependency tempdir (replaced with tempfile) and add more tests.

[CLAassistant]

All committers have signed the CLA.

[ahmedriza]

Reverted the tempdir removal. It looks like tempfile is causing SIGSEGV when loading libchdb.so in integration tests on Linux. Doesn't happen on Mac OS. I am not entirely sure why.

Also, note that the same thing happens on the current main branch too, if we try to use tempfile instead of tempdir. So it has nothing to do with any changes on this branch. In fact, the SIGSEGV happens before any Rust code is executed at all.

[wudidapaopao]

Thanks for contributing!

[austin-barrington]

Connection::open prepends CHDB_PROGRAM_NAME ("clickhouse") itself so any existing caller doing the previously-documented Connection::open(&["clickhouse", "--path=/tmp/db"]) will now produce argv ["clickhouse", "clickhouse", "--path=/tmp/db"].

This will either be handled by the clickhouse client or not, but worth noting

[wudidapaopao]

Connection::open prepends CHDB_PROGRAM_NAME ("clickhouse") itself so any existing caller doing the previously-documented Connection::open(&["clickhouse", "--path=/tmp/db"]) will now produce argv ["clickhouse", "clickhouse", "--path=/tmp/db"].

This will either be handled by the clickhouse client or not, but worth noting

Thanks for pointing this out. This works with the current chDB C API: the second "clickhouse" is effectively ignored and "--path=/tmp/db" is still parsed correctly. But I agree it is redundant.