docs: add cropping tutorial (crop_coord) (#25)

* docs: add cropping tutorial (crop_coord)

Covers crop_coord on images, layered composites, colour-range behaviour
under cropping, the contrast fix via norm, and crop_coord vs
bounding_box_query. Runs on blobs. Needs spatialdata-plot>=0.4.2.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011JMbY8asahxaytthjvCKDv

* build: require spatialdata-plot>=0.4.2, re-execute cropping on the release

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011JMbY8asahxaytthjvCKDv

* docs(cropping): switch to the Xenium cells dataset, show the zoom explicitly

Real tissue instead of blobs; box + connector lines mark the crop in
section 1 and the thumbnail; contrast section uses a dim window so the
window-vs-full stretch is visible.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011JMbY8asahxaytthjvCKDv

* docs(cropping): keep the crop box, drop the connector lines

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011JMbY8asahxaytthjvCKDv

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

Author: timtreis

_static/img/cropping.png

@@ -83,6 +83,16 @@ composite them with per-channel `palette` LUTs, fix heavy-tailed contrast
 per channel, and label the composite with `channels_as_legend`.
 :::
 
+:::{grid-item-card} Cropping a plot
+:link: /notebooks/tutorials/cropping
+:link-type: doc
+:img-top: /notebooks/_static/img/cropping.png
+
+Zoom into a bounding box with `crop_coord` — every layer windowed at draw
+time, images rasterized for the window only, and how it differs from
+`bounding_box_query`.
+:::
+
 ::::
 <!-- gallery-cards-end -->
 
@@ -98,4 +108,5 @@ as_points
 scalebars
 marker_shapes
 multichannel_images
+cropping
 ```