SRD 'Full-Round Actions - Restricted Withdraw': 'If you are limited to taking only a standard action each round you can withdraw as a standard action. In this case, you may move up to your speed.' _staggered_filter now keeps withdraw as the one move-or-standard action (spending the slot) instead of dropping it, and _flee_path halves the budget to single speed for a staggered/disabled creature (new _is_staggered_limited helper). Filter-level and engine-level tests added.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>