Add "Split image along axes" tool

[kostrykin]

Add "Split image along axes" tool that splits an image along a specific axis (e.g., channels) into a collection of separate images. This is useful, for example, to preprocess images for tools that require single-channel images.

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FOR THE CONTRIBUTOR — Please fill out if applicable

Please make sure you have read the CONTRIBUTING.md document (last updated: 2024/04/23).

• License permits unrestricted use (educational + commercial).

If this PR adds or updates a tool or tool collection:

• This PR adds a new tool or tool collection.
• This PR updates an existing tool or tool collection.
• Tools added/updated by this PR comply with the Naming and Annotation Conventions for Tools in the Image Community in Galaxy (or explain why they do not).

[Copilot]

PR Overview

This pull request adds a new tool, "Split image along axes", that splits an image along a specified axis (e.g., channels) and outputs separate images.

• Introduces a Python script that reads an image, processes axis-based splitting, and saves the outputs.
• Adds a .shed.yml file for tool metadata and updates the README.md to include the new tool.

Reviewed Changes

File	Description
tools/split_image/split.py	Implements image splitting with axis-based processing
tools/split_image/.shed.yml	Provides tool metadata for distribution
README.md	Updates tool list to include the new "Split image along axes" tool

Copilot reviewed 17 out of 17 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

tools/split_image/split.py:36

• [nitpick] The variable 'axis_pos' in the list comprehension shadows an existing variable; consider renaming it (e.g., to 'ax_idx') to avoid potential confusion.

s = [axis_pos for axis_pos in range(len(img_in.axes)) if img.shape[axis_pos] == 1 and img_in.axes[axis_pos] not in 'YX']