Add dead-simple orchestrator command with inherited run config

[mmprotest]

Motivation

• Provide a tiny orchestrator to improve long-horizon tasks by spawning scoped villani-code run subprocesses against the same live codebase while reusing the existing runner and avoiding a heavyweight framework.
• Ensure the supervisor and worker subprocesses run with the exact effective run configuration received by the parent orchestrate command so runtime/provider/debug/approval flags (current and future) are preserved and forwarded automatically.

Description

• Add villani-code orchestrate "..." CLI command that accepts the full run option surface plus orchestrator-only flags --max-workers, --max-worker-retries, --supervisor-timeout-seconds, and --worker-timeout-seconds, and prints a final JSON summary.
• Refactor shared run option wiring into typed option aliases and a single _build_inherited_run_args(...) helper used by orchestrate so all run flags are inherited and forwarded unchanged to supervisor/worker/retry subprocess constructions.
• Extend run with hidden machine-oriented flags --role, --result-json-path, and --parent-mission-id and add strict JSON artifact emission for child roles via _write_result_artifact.
• Implement minimal orchestrator modules: villani_code/orchestrator.py (orchestration flow, subprocess construction, retries, mission artifacts), villani_code/orchestrator_models.py (typed contracts), villani_code/orchestrator_roles.py (supervisor/worker prompt builders), and villani_code/orchestrator_verify.py (snapshot helpers and deterministic verification with rollback).
• Keep worker behavior effectful on the live repo (no git/worktrees), snapshot touched files before attempts, restore on failed verification, and run workers sequentially (no async or worker-to-worker chat).

Testing

• Added tests/test_orchestrator.py with focused cases for flag inheritance, forwarding to supervisor/workers/retries, supervisor retry on invalid output, worker retry and snapshot restore, non-execution of success_criteria, no final verification when no worker succeeds, parent-mission authority, and supervisor multi-subtask bounds.
• Ran the focused test suite: pytest -q tests/test_orchestrator.py tests/test_cli_debug_flags.py tests/test_cli_headless_optional_tui.py, and all tests passed (19 passed, 27 warnings).

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Codex Task