SingleFile CLI 2.15.3

CLI fixes and improvements

A JavaScript dialog opened by the page no longer stalls the capture. The browser stops the page until a dialog is answered and the CLI answered none, so an alert() in an inline script ended in "Load timeout" with no file, and one fired after load hung the process past every timeout. The dialog is now dismissed as soon as the browser reports it and the page runs on as if the user had closed it: confirm() returns false and prompt() null. A beforeunload dialog is accepted so the navigation proceeds
When a page stops answering during load, the fallback that stops the load and captures what is there is now bounded by the capture timeout instead of waiting for ever

single-file-core is updated to 1.6.8, see https://github.com/gildas-lormeau/single-file-core/releases/tag/v1.6.8. For the CLI it means that a rule written directly inside an @scope block with a selector starting with a combinator is no longer removed as unused, which restored the spacing of shared Gemini conversations; that the onbegin, onend and onrepeat handlers of SVG animation elements are removed with the other event handlers when scripts are blocked; and that the infobar's expanding ring no longer replays each time the infobar is folded back

Co-authored by Claude (Claude Code)