[php-src] PR #24653: Optimizer: array keys whose conversion may throw

Pull Request: https://github.com/php/php-src/pull/24653 Author: jorgsowa Float keys that lose precision (1.5, 1e20) emit a deprecation and resource keys emit a warning. An error handler can turn either into an exception. zend_may_throw_ex() decides whether a key type can throw, and each array-key opcode has its own copy of that list. The copies drifted apart. Before this change: | Opcode | Float key | Resource key | |----------------------------|:---------:|:------------:| | ASSIGN_DIM | ✗ | ✓ | | INIT_ARRAY | ✗ | ✓ | | ADD_ARRAY_ELEMENT | ✗ | ✓ | | FETCH_DIM_W / FETCH_LIST_W | ✗ | ✓ | | ARRAY_KEY_EXISTS | ✗ | ✓ | | FETCH_DIM_IS | ✓ | ✓ | | ISSET_ISEMPTY_DIM_OBJ | ✓ | ✗ | ✓ means zend_may_throw_ex() already counts that key type as possibly throwing; ✗ means it doesn't. After the change, every row is ✓ in both columns. Array and object keys aren't listed because every row already counted them. When it wrongly answers "cannot throw": - **JIT:** the exception check after the opcode is omitted, so execution continues past a thrown exception. - **Dead code elimination (DCE):** an unused write such as $a[1.5] = 1; is removed, so the error handler never runs. [GH-16396](https://github.com/php/php-src/issues/16396) reported the DCE case and was closed as intended optimizer behavior. However, these opcodes already treat resource keys as throwing, although they only emit a warning. A float key only emits a deprecation, so leaving it out is an oversight, not a policy. [b33e3eb8c2d](https://github.com/php/php-src/commit/b33e3eb8c2d0b10856072c93ed70c599cc8da4d1) already added float keys for FETCH_DIM_IS and ISSET_ISEMPTY_DIM_OBJ. The JIT case was not discussed in GH-16396. One shared MAY_BE_THROWING_KEY mask replaces the seven separate lists, so they cannot drift again. A follow-up for PHP-8.5 adds MAY_BE_NULL for the null offset deprecation.