Add native Rust client for YTsaurus

[styskin]

Summary

This PR introduces a native Rust SDK for YTsaurus, providing idiomatic Rust access to YTsaurus clusters.

ytsaurus-yson crate

• YSON binary format reader/writer with varint and zigzag encoding
• YSON text format reader/writer
• Full serde integration for serialization/deserialization
• Support for all YSON types: Entity, Boolean, Int64, Uint64, Double, String, List, Map

ytsaurus-client crate

• YtClient with builder pattern configuration
• Cypress operations: create, remove, exists, get, set, list, copy, move, link
• Table read/write with automatic table creation
• Token-based authentication
• Comprehensive error handling with YTsaurus error codes

Usage Example

use ytsaurus_client::{YtClient, YPath, NodeType, CreateNodeOptions};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = YtClient::builder()
        .proxy("localhost:8000")
        .token("your-token")
        .build()?;

    // Create a directory
    let path = YPath::new("//tmp/my_dir");
    client.create_node(&path, NodeType::Map, Some(CreateNodeOptions::recursive())).await?;

    // Set a value
    client.set_node(&path.join("key"), &"hello", None).await?;

    // Get a value
    let value: String = client.get_node(&path.join("key"), None).await?;
    println!("Value: {}", value);

    Ok(())
}

Test plan

• 60 unit tests for YSON serialization pass
• 17 unit tests for client functionality pass
• 6 integration tests verified against local YTsaurus cluster:
  • test_cluster_connection - connects and reads cluster name
  • test_cypress_create_and_remove - creates and removes nodes
  • test_cypress_get_set - gets and sets values
  • test_cypress_list - lists directory children
  • test_copy_move - copies and moves nodes
  • test_table_write_read - writes and reads table rows

🤖 Generated with Claude Code

[styskin]

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