Batch modularize oversized Rust test files

[yvette-carlisle]

Summary

• Split knowledge page acceptance helpers into focused helper modules.
• Split memory policy evaluation tests into support and evaluation modules.
• Split real-world benchmark boundary tests for competitor strength and trace replay reports.

Validation

• RUSTC=/run/current-system/sw/bin/rustc cargo make fmt-rust
• RUSTC=/run/current-system/sw/bin/rustc cargo make check
• RUSTC=/run/current-system/sw/bin/rustc cargo nextest run -p elf-eval --test real_world_job_benchmark adversarial_quality::adversarial_quality_fixture_catches_unsupported_and_stale_regressions --all-features (reran after one transient full-suite failure; passed)
• RUSTC=/run/current-system/sw/bin/rustc cargo make check (rerun; 403 passed, 92 skipped)