Bug: Logger class missing `warning()` method causes AttributeError

## Description

The custom `Logger` class in logger.py is missing the `warning()` method, which causes an `AttributeError` when api.py attempts to call it.

## Error Message

```
AttributeError: 'Logger' object has no attribute 'warning'
```

## Stack Trace

```
File "src/depth_anything_3/api.py", line 334, in _align_to_input_extrinsics_intrinsics
logger.warning(
^^^^^^^^^^^^^^
AttributeError: 'Logger' object has no attribute 'warning'
```

## Root Cause

In api.py line 334, the code calls `logger.warning()`:

```python
logger.warning(
"Pose alignment failed due to insufficient camera motion. "
"Using model-estimated poses and relative depth."
)
```

However, the `Logger` class in logger.py only defines `warn()`, not `warning()`:

```python
def warn(self, *args, **kwargs):
self.log("WARN:", *args, **kwargs)
```

## Suggested Fix

Add a `warning()` method as an alias to `warn()` in the `Logger` class to match Python's standard `logging` module interface:

```python
def warning(self, *args, **kwargs):
"""Alias for warn() to match standard logging interface."""
self.warn(*args, **kwargs)
```

## Environment

- Using the inference API with external extrinsics/intrinsics alignment
- Error occurs when pose alignment fails due to insufficient camera motion