Direct read_geotiff_dask on VRT drops window band and max_pixels kwargs

[brendancol]

Describe the bug

Calling read_geotiff_dask() directly on a .vrt path silently drops several kwargs. The defensive .vrt route forwards dtype, name, and chunks, but it drops window, band, and max_pixels.

Expected behavior

Direct read_geotiff_dask(vrt_path, ...) should either reject VRTs with a clear message or forward supported kwargs to read_vrt() so behavior matches open_geotiff(vrt_path, ...).

Screenshots

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Desktop

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Smartphone

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Additional context

This is a backend-dispatch parity issue in xrspatial/geotiff/__init__.py.