feat(functions): update functions tools and scorers

[Cedric / ViaDézo1er (viadezo1er)]

Summary

• add update commands for functions, tools, and scorers
• support dedicated prompt/scorer flags plus arbitrary JSON patches
• validate the effective model configuration before mutation
• materialize complete prompt_data because the backend replaces that field on PATCH
• add interactive selection, confirmation, and machine-readable output

Validation

• function update unit and CLI help tests
• cargo clippy --all-targets --all-features -- -D warnings

_{Part of GitHub stack #311}

[github-actions]

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