Fix GH-23088: Stack overflow when comparing deeply nested arrays

[lazerg]

Comparing two deeply nested arrays recurses through zend_compare_arrays -> zend_compare_symbol_tables -> zend_hash_compare once per nesting level, and nothing bounds that recursion. zend_hash_compare() only guards against cycles, so a non-cyclic array a few tens of thousands of levels deep runs the C stack out and the process dies with a segfault. === crashes the same way through zend_is_identical().

Both now check the stack limit before descending and throw an Error instead, the same way zend_std_compare_objects() already handles the object case.

Fixes GH-23088