Adopt TUnit 1.44 features: [ClassTimeline] attribute and stable TUnit.Mocks

[sliekens]

The recent upgrade of TUnit from 1.41.0 to 1.44.0 introduced several new features worth considering for the test suite.

New features

[ClassTimeline] attribute (1.43.x → 1.44.0)

Report.ExpandClassTimeline has been replaced by a [ClassTimeline] attribute that can be applied at the class level. If any test class currently uses the report-based approach, it should be migrated to the new attribute.

See: thomhurst/TUnit#5875

TUnit.Mocks promoted to stable (1.44.0)

TUnit.Mocks packages are now stable (previously experimental). The mocking API supports:

• Generated mocks in the same namespace as the mocked type
• Arg.AnyArgs() shortcut for setup/verify
• Non-span ref struct out/ref params
• Structural fixes for Mock / mocked-member name collisions

If any tests would benefit from mocking (e.g. mocking HttpClient dependencies), TUnit.Mocks is now a stable option within the TUnit ecosystem.

See: thomhurst/TUnit#5877

Performance improvements (1.43.x)

• Skip execution ledger for independent tests
• Skip tracked object graph rediscovery

These apply automatically with the upgrade — no code changes needed.

Action

• Check if any test class uses Report.ExpandClassTimeline and migrate to [ClassTimeline]
• Evaluate whether any test could benefit from TUnit.Mocks