[codex] Align SystemPrompt alias with config fields

[willccbb]

Summary

• Defines vf.SystemPrompt as PromptInput | SystemPromptConfig | None at the prompt-utils boundary.
• Uses SystemPrompt directly on v1 taskset and harness config fields and docs.
• Adds a regression for Pydantic config data resolving into SystemPromptConfig and bumps the dev version to 0.1.15.dev17.

Validation

• uv run pytest tests/test_v1_config_extension.py::test_system_prompt_alias_accepts_config_data tests/test_v1_config_extension.py::test_taskset_class_loader_owns_split_loading -q
• uv run pytest tests/test_v1_config_extension.py -q
• uv run pre-commit run --all-files
• pre-push hooks via git push -u origin codex/system-prompt-alias

---

Note

Low Risk
Typing and documentation alignment with a small validator message change; behavior is covered by existing and new config tests.

Overview
Introduces a single SystemPrompt alias as PromptInput | SystemPromptConfig | None in prompt_utils and uses it on TasksetConfig, HarnessConfig, load_system_prompt, and the API reference instead of repeating the union inline.

SystemPrompt is exported from the v1/public surface from prompt utils (removed from types). SystemPromptConfig validation is renamed/clarified (validate_one_input, clearer error). A regression test checks config dicts like {"path": "..."} coerce to SystemPromptConfig and load correctly. Dev version 0.1.15.dev17.

^{Reviewed by Cursor Bugbot for commit afcde7b. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Align SystemPrompt type alias with config fields in TasksetConfig and HarnessConfig

• Moves the SystemPrompt type alias (PromptInput | SystemPromptConfig | None) from types.py into prompt_utils.py so it co-locates with the related config and normalization logic.
• Updates system_prompt field annotations in TasksetConfig and HarnessConfig, and the return types of their load_system_prompt methods, to use the new alias instead of repeating the union.
• Renames the SystemPromptConfig validator from validate_one_source to validate_one_input and updates its error message to 'SystemPromptConfig requires exactly one of path or messages.'
• Adds a test validating that a dict with a path key is correctly aliased to SystemPromptConfig and produces normalized content.
• Behavioral Change: verifiers.v1.types.SystemPrompt is no longer defined; callers importing it from types will break.

^{Macroscope summarized afcde7b.}

[macroscopeapp]

Approvability

Verdict: Approved

Type alias alignment refactor with no runtime behavior changes. The SystemPrompt alias is moved and redefined to match the types already used by config fields. Includes a minor validator method rename and added test coverage.

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