feat: Add QueryResultOwned type for lifetime-independent streaming

[gengteng]

Implemented QueryResultOwned to solve lifetime issues encountered with streaming query results in asynchronous contexts. This type facilitates creating streams with 'static lifetimes, enabling easier integration into async workflows and structures that require static lifetime guarantees.

Key Changes:

• Added QueryResultOwned for lifetime-independent query result streaming.
• Ensured compatibility with existing streaming functionalities.

Background:
Developing async applications with the existing query streaming mechanism led to challenges due to Rust's strict lifetime requirements. Specifically, returning streams from async functions or storing them for later use was cumbersome because of lifetime ties to the client or query string.

Usage:

let query_result_owned = client.query_owned("SELECT * FROM table");
let stream = query_result_owned.stream(); // Stream with `'static` lifetime