Lingxi Form Accessibility Patch

Improves screen reader and keyboard support on Lingxi form pages.

Chrome extension that patches accessibility issues on Lingxi-generated form pages. - Adds missing page language, main/contentinfo landmarks, and mobile zoom support. - Associates visible question text with text inputs and textareas. - Gives radio and checkbox groups a programmatic group label. - Exposes required state with `aria-required` without changing the site's custom validation flow. - Prevents Tab and Shift+Tab navigation from accidentally selecting "Other" options that contain supplemental text fields. - Converts the mouse-only clear link into a keyboard-reachable button-like control. - Adds error relationships with `aria-invalid`, `aria-describedby`, and a live error summary after submit. - Adds dialog semantics and focus management to the user agreement modal. - Improves obvious contrast and focus indication issues. This is an unofficial accessibility patch for real screen reader and keyboard problems found in Lingxi-generated forms. It is a temporary mitigation, not a replacement for platform-level fixes. Lingxi should fix these accessibility issues in its own form templates so all users benefit without installing an extension.