feat: v0.2.3 — 浮动格式工具栏 + 10个新API + 德语翻译 + 类型修复

### Added
- 浮动格式工具栏：选中文本自动弹出 bold/italic/code/link/strikethrough
- 10 个新 API: getSelectedText/getCursorPosition/setCursorPosition/scrollToLine/selectLine/selectAll/replaceAll/replaceAllRegex/lineCount/getLine
- 2 个新事件: selectionChange / cursorMove
- 德语 (de) locale 完整翻译
- floatingToolbar 配置项（默认 true）

### Fixed
- onLinkClick 移除 as any，正式加入 EditorOptions/DEFAULTS
- 所有版本号统一为 0.2.3

### Tests
- core.test.ts: 183 → 214 (+31 tests)
- 总计 ~725 tests

CHANGELOG.md

@@ -2,6 +2,26 @@
 
 All notable changes to MetonaEditor will be documented in this file.
 
+## [0.2.3] - 2026-07-25
+
+### Added
+- **German (de) locale**: Complete translations for all 60+ UI keys.
+- **Floating format toolbar**: Auto-shows bold/italic/code/link/strikethrough buttons above text selection.
+- **Cursor/selection APIs**: `getSelectedText()`, `getCursorPosition()`, `setCursorPosition()`, `scrollToLine()`, `selectLine()`, `selectAll()`.
+- **Content manipulation APIs**: `replaceAll()`, `replaceAllRegex()`, `lineCount()`, `getLine()`.
+- **New events**: `selectionChange` and `cursorMove` emitted for cursor/selection tracking.
+- **`floatingToolbar` config option**: Enable/disable floating toolbar (default `true`).
+
+### Changed
+- **`floatingToolbar` added to `DEFAULTS` and `EditorOptions` type**.
+- **6 locales now**: zh-CN, en-US, ja, ko, fr, de.
+
+### Fixed
+- **`onLinkClick` type fix**: Removed `as any` cast; properly typed in `EditorOptions` and `DEFAULTS`.
+- **Version consistency**: All files synced to 0.2.3.
+
+---
+
 ## [0.2.2] - 2026-07-25
 
 ### Added