Pointcut ids depend on registration order (PointcutBuilder::$index static counter)

[lisachenko]

Problem

src/Aop/Support/PointcutBuilder.php:31 keeps a private static int $index auto-increment used to build pointcut ids. Those ids become container keys and end up in the advisor cache, so id stability depends on aspect registration order across the whole process — two hosts registering aspects in different order produce incompatible caches, and a shared/prebuilt cache can silently mismatch.

Proposed change (for discussion)

• Instance-scope the counter, or better: derive the id deterministically by hashing the pointcut expression + declaring aspect (stable across processes and registration order).
• Consider a cache-format version bump if id shape changes (interacts with the advisor-cache RFC).

Effort S, risk low. Registered for tracking; interplay with the opcache-friendly advisor cache RFC should be settled first.