Raise the initial JS gzip budget for the keyboard focus-ring fix

The keyboard-only focus input hook and the MutationObserver-based
focus-trap recovery are real, load-bearing code, not bloat, and push
the initial bundle about 150 bytes past the previous 80,000 B gzip
ceiling. Raise it to 80,500 B rather than trim functional code.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>