fix: validate lifecycle backtest execution results

[Pigbibi]

Summary

• Pass supported lifecycle parameters into the executed strategy configuration and reject unsupported fields.
• Record the observed return count and actual return window.
• Reject malformed observed returns before producing ordinary metrics while preserving leading warmup NaNs.

Validation

• Python 3.12 CI dependency lock (requirements-lock.txt): targeted unittest discovery passed (7 runner tests, 11 metric tests).
• Existing uv.lock frozen environment: targeted pytest passed (18 tests).
• git diff --check passed.

No dependency or lockfile changes.