[Fix] th-cli --version Surfaces Backend And SDK Versions (#999)

[abhisheksingh-esp]

Summary

Fixes #999. th-cli --version now surfaces the backend and SDK versions returned by GET /api/v1/version.

Root cause

get_versions() in th_cli/utils.py was annotated -> dict but actually returned a Pydantic TestHarnessBackendVersion instance from the autogenerated SyncVersionApi. The caller in main.py::get_extended_help iterated it with .items(), which raised AttributeError on the model. The bare except Exception: swallowed it and replaced the block with "Not able to retrieve versions from server.", so the five backend fields (version, sha, sdk_sha, sdk_docker_tag, db_revision) were dropped CLI-side even though the API response was fine.

Fix

Convert the Pydantic v2 model to a dict via model_dump() in get_versions(). The existing .items() loop in get_extended_help then renders all backend fields without further changes.

[gemini-code-assist]

Code Review

This pull request updates the get_versions function in th_cli/utils.py to return a dictionary representation of the version information using model_dump(). The reviewer suggested using model_dump(mode='json') to ensure that any future complex data types are correctly serialized for JSON output, which improves the robustness of the CLI utility.

[gemini-code-assist]

Consider using model_dump(mode='json') instead of model_dump(). While the current fields in TestHarnessBackendVersion are all strings, using mode='json' ensures that any future complex types (like datetimes or enums) are automatically serialized to JSON-compatible formats. This makes the function more robust for its intended use in the CLI, where the results are likely to be printed or serialized.

Suggested change

	return versions_info.model_dump()
	return versions_info.model_dump(mode='json')