Support specifying commit in execution/task node definition

[akx]

Required for supporting library steps

[Copilot]

Pull Request Overview

This PR adds support for specifying a commit in execution and task node definitions to enable library steps functionality. This allows pipeline nodes to reference steps from different commits or external libraries rather than only the current project's steps.

• Added commit property to execution and task node schemas and implementations
• Refactored schema definitions to eliminate code duplication between execution and task nodes
• Updated linting logic to skip step validation when a commit is specified

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
valohai_yaml/schema_data.py	Refactored schema definitions and added commit property support
valohai_yaml/objs/pipelines/execution_node.py	Added commit parameter and updated linting logic
tests/test_pipeline.py	Added test for pipeline with commit functionality
tests/conftest.py	Added test fixture for commit-based pipeline
tests/snapshots/test_validation.ambr	Updated error message formatting with quotes
examples/pipeline-with-different-commit.yaml	Added example configuration showing commit usage

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[Copilot]

Converting commit to string when it's not None could cause issues if commit is already a string or if it's an unexpected type. Consider using self.commit = commit directly since the type hint indicates it should be Optional[str].

Suggested change

	self.commit = str(commit) if commit else None
	self.commit = commit

[ruksi]

looks simple enough, the more complex part is the other side of the implementation 😆