Standardize Cargo workspace edition and resolver configuration

[slfan1989]

Summary

Upgrade the Cargo workspace configuration to use resolver version 2 for better dependency resolution.

Changes

• Add resolver = "2" to the workspace configuration in Cargo.toml

Benefits

• Resolver 2 is the default resolver for Rust 2021 edition
• Provides improved dependency version resolution strategy
• Avoids known issues with the legacy resolver
• Recommended best practice for workspace projects

Impact

• No breaking changes expected
• Dependencies will be resolved using the newer, more robust algorithm