fix(assembly-syntax): canonicalize PathBuf::try_from(String)

[KitaroMoha563]

Describe your changes

• Canonicalize PathBuf::try_from(String) by delegating to PathBuf::new, so it matches TryFrom<&str> and FromStr.
• Add a regression test in path_buf.rs to ensure PathBuf::try_from("foo::\"bar\"".to_string()) is equal to PathBuf::try_from("foo::\"bar\"") and canonicalizes to foo::bar.
• This fixes inconsistent equality/hashing behavior for semantically equivalent paths created from different conversion APIs.

Checklist before requesting a review

• Repo forked and branch created from next according to naming convention.
• Commit messages and codestyle follow conventions.
• Commits are signed.
• Relevant issues are linked in the PR description.
• Tests added for new functionality.
• Documentation/comments updated according to changes.
• Updated `CHANGELOG.md'

[github-actions]

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• e747f98b fix(assembly-syntax): canonicalize PathBuf::try_from(String)

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[github-actions]

Automated check (CONTRIBUTING.md)

Findings:

• Link an issue in the PR body (e.g., "Fixes Implement SHA256 in Miden Assembly #123").
• Add a short Rationale explaining why the change is needed.

Recommendations:

• Consider adding a Test plan or clear review steps.

Next steps:

• Link a relevant issue (e.g., "Fixes Implement SHA256 in Miden Assembly #123") and ensure it is assigned to you.
• See CONTRIBUTING.md for expectations.
• If this is a false positive, comment: /quality-review.

[bitwalker]

This will always reallocate, we only want to reallocate if we need to

[KitaroMoha563]

@bitwalker Updated. Please take another look, thanks for your time.