fix(release): support version-based engine reuse and fix Cargo.toml indent matching

[NathanFlurry]

Description

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Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

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[NathanFlurry]

• fix(release): support version-based engine reuse and fix Cargo.toml indent matching #4288 👈 (View in Graphite)
• main

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[claude]

PR Review: fix(release): support version-based engine reuse and fix Cargo.toml indent matching

Summary

This PR adds support for reusing version-tagged Docker manifests and S3 artifacts (not just commit-tagged ones), fixing a chain-release scenario where a previous release itself reused artifacts from an even earlier release. It also fixes a Cargo.toml regex that was failing when the workspace.package section had leading whitespace.

The overall approach is sound. The separation between version-based and commit-based artifact paths is clear and consistent across docker.ts, promote-artifacts.ts, and main.ts.

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Bug: Docker image name mismatch

The validateReuseVersion function in main.ts checks rivetkit/engine, but the REPOS array in docker.ts publishes to rivetdev/engine. The validation would always fail (or silently pass against the wrong registry) at runtime. Worth confirming whether rivetkit/engine is an intentional org migration or an oversight.

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Minor: Misleading parameter name in promotePath

After this PR, the sourceCommit parameter in promotePath can hold a version string like 2.0.33, not just a commit hash. Renaming to sourcePrefix or sourceRef would match the call-site variable name and avoid confusion.

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Positive: --latest auto-detection

Removing the hardcoded true default and replacing it with shouldTagAsLatest auto-detection is a good improvement. The guard if opts.latest is not undefined correctly handles explicit --latest/--no-latest overrides while defaulting to semver-based auto-detection.

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Positive: Cargo.toml regex fix

The updated regex captures leading whitespace in a capture group and restores it via backreference in the replacement string. The prior regex would silently strip indentation when workspace.package appeared inside a nested TOML context with leading whitespace.

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Observation: Version vs commit detection heuristic

Using .includes('.') to distinguish version strings from commit hashes is applied consistently across all three files and matches the existing versionOrCommitToRef utility. Works correctly for the expected inputs (2.0.33 vs bb7f292). A semver regex would be more defensive but is likely overkill for this controlled context.

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Verdict

The architecture is correct and the refactor is clean. The main issue worth addressing is the Docker org name mismatch (rivetkit/engine vs rivetdev/engine) in validateReuseVersion.