[13.x] Support enum queue names in QueueFake

[Tresor-Kasenda]

Queue names passed as UnitEnum values are now normalized before being stored or queried, so fake queue assertions and inspection APIs behave consistently with string queue names.

Changes

• Normalize queue names with enum_value() in QueueFake::push(), pushRaw(), size(), and pendingJobs().
• Update queue-related docblocks to accept UnitEnum|string|null.
• Add coverage for enum queue names with size, pendingJobs, bulk, pushOn, laterOn, and raw pushes.