Fix double-free of closure run_time_cache in partial application#22790
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A partial over a closure whose op_array is not persistent shallow-copies the closure's op_array into the per-request PFA cache as a lifetime anchor. The copy inherited ZEND_ACC_HEAP_RT_CACHE and the run_time_cache pointer, so destroy_op_array() freed the closure's cache twice: once when the closure was released and again at PFA cache teardown. Use function_add_ref() for the copy, which resets the per-request run_time_cache and static_variables_ptr map pointers, so only the live closure owns and frees the cache.
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A partial built over a closure whose op_array is not persistent (created in eval() or via the CLI -r path, or when opcache is not caching the declaring script) makes zend_accel_compile_pfa shallow-copy the closure op_array into the per-request PFA cache as a lifetime anchor. The copy inherited ZEND_ACC_HEAP_RT_CACHE and the run_time_cache pointer, so destroy_op_array freed the shared run_time_cache twice: once when the closure was released and again at PFA cache teardown, corrupting the heap. Use function_add_ref() on the copy, the canonical shallow-copy refcount helper, which resets the per-request run_time_cache and static_variables_ptr map pointers so only the live closure owns and frees the cache.
Reproducer, invalid free under valgrind (USE_ZEND_ALLOC=0) before the fix, clean after:
php -d opcache.enable_cli=1 -r 'class C { function m($x,$y){ return $x+$y; } } $cl = Closure::fromCallable([new C,"m"]); $pc = $cl(10,?); var_dump($pc(5));'