Rust: allow shadowing of prelude items

[aibaars]

@hvitved

[Copilot]

Pull Request Overview

This PR updates the Rust test file to explicitly allow shadowing of prelude items by introducing a new type alias Result along with an int_div function for demonstrating the behavior.

• Introduces a new type alias Result that aliases std::result::Result<T, String>.
• Adds a function int_div that leverages the new type alias to handle division, returning an error on division by zero.

Files not reviewed (3)

• rust/ql/lib/codeql/rust/internal/PathResolution.qll: Language not supported
• rust/ql/test/library-tests/path-resolution/path-resolution.expected: Language not supported
• rust/ql/test/library-tests/path-resolution/path-resolution.ql: Language not supported

Comments suppressed due to low confidence (1)

rust/ql/test/library-tests/path-resolution/my.rs:20

• [nitpick] While the PR's intent is to allow shadowing of prelude items, consider whether a more descriptive alias (e.g., MyResult) might improve code clarity for future readers.

type Result<

[hvitved]

LGTM, assuming DCA is happy (I have started a run).