#1290 feat(version-manager): add side-effect-free version resolution

Summary

• Add version-manager resolve <versionTags...> to print the highest matching version.
• Skip generator bootstrap and downloads for the resolver command.
• Keep configuration reads side-effect-free so openapitools.json is not created or modified.

Testing

• yarn lint
• yarn test
• yarn build
• Manual check: version-manager resolve latest prints 7.26.0 without creating a config file or JAR.

Fixes #1289

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Summary by cubic

Adds a side-effect-free resolve subcommand to version-manager that prints the highest matching version, fixing #1289. Resolution now fails with a non-zero exit code when no version matches the given tags.

• version-manager resolve <versionTags...> prints the first matching version and skips generator bootstrap, downloads, and config writes; unmatched tags print an error to stderr and exit non-zero.
• The command is detected positionally, so opening flags like --openapitools are skipped and it is not confused with pass-through arguments.
• ConfigService no longer creates or modifies openapitools.json when reading configuration—the file is only touched on writes.