PHP coerces numeric-string array keys ("1") to int keys, so ids()/each()/clear()
could hand ints to remove(string) and TypeError. Cast to string in those paths.
Surfaced by the laravel-ws integration (connection ids are sequential numbers).
Regression test added. Suite: 20 tests.
rel learn-atc #1055#1057
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>