Introduce canonicalization library for Windows subst drives

[jketema]

See internal PR for a full explanation.

[Copilot]

Pull request overview

Adds Windows subst drive canonicalization to Go and Java/Kotlin extraction paths.

Changes:

• Loads and invokes canonicalize.dll from Go and Java.
• Adds the Go Windows-system dependency and Bazel wiring.
• Updates cross-language integration expectations for canonical paths.

Show a summary per file

File	Description
MODULE.bazel	Exposes the Go Windows dependency.
go/extractor/extractor.go	Resolves subst paths during normalization.
go/extractor/util/subst_windows.go	Implements Windows DLL integration.
go/extractor/util/subst_other.go	Adds the non-Windows no-op.
go/extractor/util/BUILD.bazel	Builds platform-specific resolver sources.
go/extractor/go.mod	Adds x/sys.
go/extractor/go.sum	Records dependency checksums.
java/kotlin-extractor/src/main/java/com/semmle/util/files/SubstResolver.java	Adds Java native resolution.
java/kotlin-extractor/src/main/java/com/semmle/util/files/FileUtil.java	Applies resolution during canonicalization.
go/ql/integration-tests/subst/file.expected	Updates Go expected paths.
java/ql/integration-tests/java/subst/file.expected	Updates Java/Kotlin expected paths.
javascript/ql/integration-tests/subst/file.expected	Updates JavaScript expected paths.
python/ql/integration-tests/subst/file.expected	Updates Python expected paths.
ruby/ql/integration-tests/subst/file.expected	Updates Ruby expected paths.
rust/ql/integration-tests/subst/file.expected	Updates Rust expected paths.
csharp/ql/integration-tests/windows/subst/file.expected	Updates C# expected paths.

Review details

• Files reviewed: 15/16 changed files
• Comments generated: 2
• Review effort level: Medium

[geoffw0]

LGTM, subject to the internal PR getting approval, tests passing etc.

👍

[jketema]

@geoffw0 could you re-approve? Note that the tests here cannot pass, because of the dependency on the internal PR.

[geoffw0]

It's not the tests that slowed me down, it's the force push. I'll check it over now and re-approve...

[jketema]

My test remark was a comment on:

LGTM, subject to the internal PR getting approval, tests passing etc.

Apologies for the force push, but it's just the easiest way to resolve submodule conflicts.

The only thing new after the force push is 726705b, which is in line with the internal changes.

[geoffw0]

👍

[geoffw0]

Yep, I see the internal PR is now approved and has passing tests. 👍