VRT source reads do not honor max_pixels safety limit

[brendancol]

Describe the bug

read_vrt(..., max_pixels=...) caps the assembled VRT output and some resample intermediates, but it does not pass max_pixels into the source GeoTIFF reads. A VRT can request a small output or destination rect while forcing a much larger source SrcRect decode, bypassing the caller's safety budget.

Expected behavior

The max_pixels limit should apply to every materialized source window and intermediate created while reading a VRT, not just the final VRT output.

Screenshots

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Desktop

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Smartphone

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Additional context

The source read in xrspatial/geotiff/_vrt.py calls read_to_array(...) without forwarding max_pixels.