chore: update Rust toolchain to 1.92

[DaleSeo]

Motivation and Context

This PR updates the Rust toolchain in the repository from 1.90 to 1.92 (the current stable version is 1.94.1) and address issues based on the updated Clippy's default rules.

This follows a sequence of related fixes where release-plz checks were still failing due to toolchain/version interactions:

• ci: use release-plz fork with semver_check_features #776
• ci: add --locked to release-plz install #786
• fix: upgrade rustc in actions #796

Even after those, we still had mismatch behavior between workflow setup and repo toolchain override. This PR makes the repo/toolchain baseline explicit and consistent by bumping the pinned repo toolchain itself.

How Has This Been Tested?

Breaking Changes

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context