[Bug]: AbortError is ignored — calculate_status has the abort branch commented out

### What happened?

apalis-postgres 1.0.0-rc.8 with apalis 1.0.0-rc.9.

In src/ack.rs the abort branch is commented out:

Err(e) => match &e {
// Error::Abort(_) => State::Killed,
_ if parts.ctx.max_attempts() as usize <= parts.attempt.current() => Status::Killed,
_ => Status::Failed,
},

Every Err becomes Status::Failed and the task is refetched until max_attempts (5 by default). There is no way to tell this backend a task must not be retried.

The two retry layers also disagree. apalis-core's BackoffRetryPolicy::retry does honour it:

Err(err) if (err as &dyn Any).downcast_ref::().is_some() => None,

The in-process tower retry stops correctly, then the storage layer refetches the task anyway. RetryPolicy::retry_if has the same problem: the predicate returns false, no in-process retry happens, and the job still runs 5 times.

Repro: a task fn that always returns Err(AbortError::new(...)) against PostgresStorage. Observe 5 executions and attempts = 5.

This makes non-idempotent tasks unsafe — anything with an external side effect gets repeated 5 times even when the failure is known to be permanent.

### Expected behavior

Returning AbortError from a task fn settles the task as Killed after one attempt, with no refetch.

### Steps to reproduce

1. Build a worker on PostgresStorage with a task fn that always returns
Err(AbortError::new("permanent")).
2. Push one task and run the worker.
3. The task executes 5 times instead of once. The row ends at attempts = 5,
and every intermediate ack wrote Status::Failed instead of Killed.

Same result with RetryPolicy::retries(n).retry_if(|_| false) — the predicate
returns false, so the tower layer never retries, but the storage layer refetches
the task anyway.

### Minimal code example

```rust

```

### Version

1.0.0-rc.x

### Environment

- OS: Fedora Linux 44 (Workstation Edition)
- Rust version: 1.97.1
- Cargo version: 1.97.1

### Relevant log output

```shell

```

### Additional context

_No response_

Start in src/ack.rs at calculate_status and then read the storage retry path alongside BackoffRetryPolicy::retry and RetryPolicy::retry_if. Run the described PostgresStorage reproduction with a task returning AbortError and verify that it executes once, is acknowledged as Killed, and is not refetched.

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