feat: list asynchronous actions with pollora:async:list

[ogorzalka]

Phase 4 of Async Actions, step 2: pollora:async:list [--json].

• Every asynchronous action (from ->async() and #[Async], read through AsyncInspector from feat: check asynchronous actions in pollora:doctor and Site Health #430): hook, priority, handler, driver (via or default), delay, attempts and backoff, unique lock, queue, as user.
• Which drivers are available in this request, with the reason when one is not.
• The default driver and where it comes from: HOOKS_ASYNC_DRIVER, the POLLORA_ASYNC_DRIVER constant, the pollora/hook/async_driver filter, or auto and the drivers it tries.

AsyncServiceProvider::autoDrivers() now holds the auto order, used by the provider and the command.

Tests: AsyncListCommandTest (3). Full suite and PHPStan green.