Add extra Customizations files

[knewbury01]

for languages that do not have a Customizations file, add one

[Copilot]

Pull Request Overview

This PR adds Customizations.qll files to three languages (Swift, Rust, and C++) that previously lacked them, following the established pattern used in other CodeQL language packs. The customizations infrastructure allows users to extend the standard library with their own models and customizations.

• Adds new Customizations.qll files for Swift, Rust, and C++
• Updates the main language pack files to import the new Customizations modules
• Provides consistent infrastructure across languages for user-defined customizations

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
swift/ql/lib/swift.qll	Adds import statement for Customizations module
swift/ql/lib/Customizations.qll	Creates new customizations file with documentation and swift import
rust/ql/lib/rust.qll	Adds import statement for Customizations module
rust/ql/lib/Customizations.qll	Creates new customizations file with documentation and rust import
cpp/ql/lib/cpp.qll	Adds import statement for Customizations module
cpp/ql/lib/Customizations.qll	Creates new customizations file with documentation and cpp import

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[jketema]

LGTM. Could you add three library change notes though (one for each language). See https://github.com/github/codeql/blob/main/docs/change-notes.md

[geoffw0]

👍