fix parsing rules crash

[killown]

fix #2957

[killown]

EE 2026-01-17 10:18:05.569 - [plugins/window-rules/window-rules.cpp:202] Error parsing rule: on created if app_id contains "Alacritty" then set alpha  Exception: basic_string::at: __n (which is 57) >= this->size() (which is 57)
EE 2026-01-17 10:18:05.570 - [plugins/window-rules/window-rules.cpp:202] Error parsing rule: on created if app_id contains "Alacritty" then set alpha  Exception: basic_string::at: __n (which is 57) >= this->size() (which is 57)
EE 2026-01-17 10:18:06.505 - [plugins/window-rules/window-rules.cpp:202] Error parsing rule: on created if app_id contains "Alacritty" then set alpha  Exception: basic_string::at: __n (which is 57) >= this->size() (which is 57)
EE 2026-01-17 10:18:06.506 - [plugins/window-rules/window-rules.cpp:202] Error parsing rule: on created if app_id contains "Alacritty" then set alpha  Exception: basic_string::at: __n (which is 57) >= this->size() (which is 57)

[killown]

Closed, as @ammen99 fixed the issue in wf-utils.