[php-src] PR #25374: Fix stale PFA cache entries after the declaring site is freed

Pull Request: https://github.com/php/php-src/pull/25374 Author: jorgsowa The request PFA cache is keyed on the address of the declaring site (&opline->lineno or &ast->lineno). Without SHM caching, this memory can be freed while the cache entry is still alive: - eval()'d op_arrays are freed after execution - class constant ASTs are freed after evaluation A later PFA allocated at the same address then hits the stale entry and gets an op_array compiled for a different argument shape. This leads to wrong bound arguments, or out-of-bounds writes in zp_bind() when the bound var counts differ. Fix: - Runtime PFAs: the cached op_array retains the declaring op_array via dynamic_func_defs, like it already does for called closures. - Const expr PFAs with a non-interned name: key on the name, which is unique per declaration and kept alive by the cached op_array's function_name. Interned names mean the AST is in persistent memory, so the address key is kept. Trade-off: PFAs in eval()'d code keep that op_array alive until the end of the request.