feat: add R1 timing semantics to BacktestOrchestrator

[Pigbibi]

R1-S2

• spec_digest: r1-owner-freeze-20260714-s1
• base_sha: 9039d59
• supports explicit next_open/next_close timing
• preserves legacy runners when timing is omitted
• adds persist=false ephemeral mode; no artifact generation or external data

Non-goals

No real input acquisition, persistence in ephemeral mode, broker/order/account/funds, shadow/canary/live, paid API, or strategy optimization.

Validation

PYTHONPATH=src python3 -m pytest -q tests/test_backtest_orchestrator.py tests/test_param_optimizer.py (14 passed)
PYTHONPATH=src python3 -m compileall -q src/quant_platform_kit/strategy_lifecycle
python3 -m ruff check ... and git diff --check

[github-actions]

🤖 Codex PR Review

🚫 Merge blocked: 2 serious issue(s) found in high-risk files

🚫 Blocking Issues

These issues must be fixed before this PR can be merged:

1. 🟠 [HIGH] Bug in src/quant_platform_kit/strategy_lifecycle/contracts.py

BacktestResult inserts the new execution_timing dataclass field in the middle of the existing positional field order, before all metric fields. Any existing code that constructs BacktestResult positionally will now silently shift later arguments (for example, a previous positional sharpe_ratio value will land in execution_timing), causing corrupted results instead of an immediate failure. (line 230)

Suggestion: Preserve positional compatibility by appending execution_timing at the end of the dataclass fields, or make new fields keyword-only so older positional call sites keep their original meaning.

2. 🟠 [HIGH] Logic in src/quant_platform_kit/strategy_lifecycle/backtest_orchestrator.py

_run_runner() treats explicit support for execution_timing/persist as "parameter name must appear in inspect.signature(...)". That rejects runners implemented with **kwargs, even though those runners can legitimately accept and forward the new arguments. As a result, existing wrapper/adaptor runners that were intentionally forward-compatible will fail with TypeError when the new features are used. (line 142)

Suggestion: When checking runner capability, treat a VAR_KEYWORD (**kwargs) parameter as supporting these optional arguments, or optimistically call the runner and only translate an actual unexpected-keyword TypeError into the compatibility error.

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Review by Codex PR Review bot • PR

[chatgpt-codex-connector]

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