Add controlled cross-framework comparator execution

[josiahking]

Summary

• add controlled comparator execution for EvolvePHP, Laravel, Symfony, Slim, and Phalcon
• enforce runtime identity, provenance capture, isolated worker execution, and comparable scenario timing boundaries
• add deterministic cold-boot scheduling with rotating framework order and discarded pre-measurement workers
• strengthen comparator availability, normalization, documentation, and regression coverage

Validation

• benchmark syntax, PHPUnit, benchmark smoke, and all five comparator smoke checks pass
• root architecture, PHPStan, coding-style, and PHPUnit checks pass
• package split, release package, skeleton/create-project, prerelease consumer, and supply-chain validation pass
• controlled PHP 8.4.25 evidence was generated with OPcache CLI enabled and JIT disabled

No broad performance-ranking claim is made from the comparator data.