perf(runner): transfer provider args without codecs

[Chemaclass]

🤔 Background

Related #1370

Provider-heavy suites spend time encoding and decoding every argument. Pass arguments without those codec processes while keeping the public provider API and evaluation rules.

💡 Changes

• Preserve empty values, quoting, newlines and parser isolation through run-owned argument storage.
• Restore missing storage between rows and report setup, write or read failures instead of losing tests or arguments.
• Cover argument fidelity, isolation, cleanup, storage failures and zero per-argument codec calls. Update the changelog.
• Local source, standalone, static and formatting gates pass. On macOS Bash 3.2, 100 two-argument rows take 817 ms instead of 1,898 ms; one/eight-argument and large-value checks also improve. Medians use five alternating pairs against main at f33a9ac with the same paths and fixtures.