fix: resolve clippy warnings across workspace

[DaleSeo]

Motivation and Context

The PR resolves all the Clippy errors and warnings in the codebase.

How Has This Been Tested?

Breaking Changes

None.

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

[jamadeo]

Hey @DaleSeo what clippy config/version are you running with? The clippy step in CI runs with -D warnings, but it's passing.

[DaleSeo]

@jamadeo Yes, it uses -D warnings, but --all-features enables local, which excludes test files that start with #![cfg(not(feature = "local"))]. I added a new Clippy check to prevent warnings like this from slipping through:

rust-sdk/.github/workflows/ci.yml

Lines 67 to 73 in 7b4e093

	- name: Run clippy (all features except local)
	run: |
	FEATURES=$(cargo metadata --no-deps --format-version 1 \
	| jq -r '[.packages[] | select(.name == "rmcp") | .features | keys[]
	| select(startswith("__") | not)
	| select(. != "local")] | join(",")')
	cargo clippy --package rmcp --all-targets --no-default-features --features "$FEATURES" -- -D warnings