The floating bubble menu had no way to clear formatting, so in the
default configuration (fixed toolbar disabled) users could not reset
inline formatting at all. Mirror the fixed-toolbar action into the
bubble menu: a new "Clear formatting" item running unsetAllMarks().
- bubble-menu.tsx: import IconClearFormatting; append a non-toggle
"Clear formatting" item (isActive: () => false) to the items array.
- No i18n changes — the "Clear formatting" key already exists in all
locales.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>