[BUG] Map.fly_to raises if you pass a numpy.int64 for zoom

## Context

I called `Map.fly_to` and passed a value for `zoom` that was a `numpy.int64`.

## Resulting behaviour, error message or logs

A type error got raised because of the `numpy.int64`. The type checking in the `fly_to` is overly restrictive and explicitly checks for a normal `int` or `float`:

```python
if not isinstance(zoom, (int, float)):
raise TypeError(f"Expected zoom to be an int or float, got {type(zoom)}")
```

I recommend instead trying to cast the value for zoom (and latitude and longitude) to floats and only raising if that fails.

## Environment

- OS: Windows 11
- Browser: Firefox
- Lonboard Version: 0.12.1 (though I see it's still present in 0.13.0)

## Steps to reproduce the bug

```python
import geopandas as gpd
import numpy as np
from shapely.geometry import Point

import lonboard

d = {'col1': ['name1', 'name2'], 'geometry': [Point(1, 2), Point(2, 1)]}
gdf = gpd.GeoDataFrame(d, crs="EPSG:4326")
layer = lonboard.ScatterplotLayer.from_geopandas(gdf)
map_ = lonboard.Map(layers=[layer])

map_.fly_to(longitude=0, latitude=0, zoom=np.int64(2))
```

Thank you for all of your efforts on lonboard. This library has been extremely helpful for a project that I'm currently working on that involves plotting large shapefiles.

Start from the Map.fly_to implementation and reproduce the supplied example with numpy.int64(2). Check how zoom, latitude, and longitude are validated; done means numpy numeric values are accepted while values that cannot be converted still raise an appropriate error.

Written by the indexing model from the issue text.