Add compute_workgroups example

[mrinalchaturvedi27]

This PR adds a compute_workgroups.py example demonstrating GPU workgroups and invocation IDs.
While reviewing the WGPU documentation and the Rust hello_workgroups example, I noticed that wgpu-py does not include a focused example for workgroups.
This example provides a minimal compute shader that writes global_invocation_id, local_invocation_id, and workgroup_id into a storage buffer so the relationship between them can be inspected.

[Copilot]

Pull request overview

Adds a new compute_workgroups.py example to the examples/ suite to help users understand how compute workgroups relate to invocation IDs in wgpu-py, by writing invocation/workgroup identifiers into a storage buffer and printing/verifying the mapping on the CPU.

Changes:

• Add a minimal WGSL compute shader that records global_invocation_id, local_invocation_id, and workgroup_id (currently x-components) into a storage buffer.
• Add a Python driver that dispatches workgroups, reads back the buffer, prints a table, and validates the expected ID relationships.

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[Copilot]

The docstring says each thread writes its global/local/workgroup IDs, but the shader only writes the .x component of each builtin (y/z are always 0 with the current 1D dispatch). Consider clarifying in the docstring that this example records the x-components (or expand the buffer to store all 3 components per ID).

Suggested change

	Each thread writes its global, local, and workgroup IDs into a storage buffer
	so the relationship between them can be inspected.
	Each thread in this 1D dispatch writes the x-components of its global, local,
	and workgroup IDs into a storage buffer so the relationship between them can
	be inspected.

[Copilot]

There’s an extra trailing space at the end of the header format string, which results in an extra space in the printed table header. Consider removing it to keep output tidy.

Suggested change

	print(f"{'Thread':>6} {'global_id':>9} {'local_id':>8} {'workgroup_id':>12} ")
	print(f"{'Thread':>6} {'global_id':>9} {'local_id':>8} {'workgroup_id':>12}")

[mrinalchaturvedi27]

Hi @Korijn @almarklein, just checking in on this PR. Whenever you get a chance, could you please take a look? Happy to make any changes if needed. Thanks!