CameraOptions padding does not work

Nobody has claimed this yet.

The padding property of CameraBounds is ignored when calculating coordinate bounds.

This makes it impossible to detect which areas of the map are clear of obstructions like floating buttons and toolbars.

**To reproduce:**

```
CameraState c = await mapboxMap.getCameraState();

// get a bounds with padding
var borderPixels = 20.0;
final b1 = await mapboxMap.coordinateBoundsForCamera(CameraOptions(
padding: MbxEdgeInsets(
top: borderPixels,
left: borderPixels,
bottom: borderPixels,
right: borderPixels,
),
center: c.center,
zoom: c.zoom,
pitch: c.pitch,
));

// get a bounds without padding
final b2 = await mapboxMap.coordinateBoundsForCamera(CameraOptions(
center: c.center,
zoom: c.zoom,
pitch: c.pitch,
));

// the coordinates should be different but are the same
bool neSame = b1.northeast.coordinates == b2.northeast.coordinates;
bool swSame = b1.southwest.coordinates == b2.southwest.coordinates;

print('neSame: $neSame'); // prints true
print('swSame: $swSame'); // prints true

```

**Expected behaviour:**

The padding should be applied to the bounds returned.

Start at the coordinateBoundsForCamera entry point and trace how CameraOptions padding is handled. Reproduce the issue with the provided Flutter example, comparing bounds with and without padding; the fix is complete when the returned bounds reflect the specified padding.

Written by the indexing model from the issue text.