- update blockRegistry to accept ReactNode icons instead of emoji strings
- replace emoji icons in all built-in block types with icon components from shared icons
- add `isHexColor` and `collectUsedColors` helpers to inline/types.js
- extend `color` and `highlight` marks to accept hex color strings in addition to palette keys
- pass `usedColors` (collected from document) to InlineToolbar
- update InlineToolbar color popover to show used colors and a free color input
- add new icons to shared icons index
- update README to reflect icon, color, and toolbar popover changes
- move `e.preventDefault()` from toolbar container to each individual button to avoid broad focus prevention
- default `linkNewTab` state to `false` instead of `true` for new links
- add `onMouseDown` prevention to color grid buttons
- add `linkNewTab` state (default true) in InlineToolbar
- pass `newTab` flag through `onToggleMark` on link submit and remove
- restore `newTab` value when reopening the link popover
- add checkbox ui in link popover to toggle new tab behavior
- update link serialization to render `target="_blank" rel="noopener noreferrer"` when `newTab` is set
- add `newTab` field to link mark type definition
- add `toolbarPinnedRef` in BlockEditor to prevent toolbar from closing while a popover is focused
- pass `onPinChange` callback to InlineToolbar to toggle the pinned state
- notify parent via `onPinChange` whenever popover state changes
- remove rect-change effect that was incorrectly closing popovers on selection update
- migrate block content from plain strings to InlineNode[] structure
- add inline toolbar (bold, italic, code, color, link) on text selection
- add checklist block type with toggle support
- add image block type (URL-based, phase 2)
- add inline serialization helpers (inlineToDom, domToInline)
- add inline types and length utilities
- extend caret utils with range get/set support
- update block registry and all existing block types for new content model
- update demo blocks in ComponentsPage to use rich inline content
- update README to reflect new architecture
hykocx