release: v0.4.3 — 版本号更新与预览区文本选择修复

- 版本号从 0.4.2 升级至 0.4.3
- 修复预览区内容无法鼠标拖拽选择/复制的问题
- 根因：html/body 上的 user-select: none 级联到预览面板
- 修复：为 .me-preview 及其子元素恢复 user-select: text

src/renderer/styles/global.css

@@ -128,6 +128,22 @@ body {
   height: 100%;
 }
 
+/* FIX: Allow text selection in the preview pane.
+   global.css sets user-select:none on html/body to prevent
+   selection in UI chrome (toolbar, tabs, sidebar), but this
+   also blocked mouse-drag selection in the Markdown preview.
+   Override back to the browser default for the preview area. */
+.metona-editor-wrapper .me-preview,
+.metona-editor-wrapper .me-preview * {
+  user-select: text;
+}
+
+/* Also restore selection in the editor textarea (MetonaEditor
+   explicitly sets user-select:none on it in some themes) */
+.metona-editor-wrapper textarea {
+  user-select: text;
+}
+
 /* Tab Bar */
 #tab-bar {
   height: 36px;

src/shared/constants.ts

@@ -1,5 +1,5 @@
 // 共享常量 — 主进程和渲染进程共用
-export const APP_VERSION = 'v0.4.2'
+export const APP_VERSION = 'v0.4.3'
 export const MAX_FILE_SIZE = 20 * 1024 * 1024 // 20MB
 export const ALLOWED_EXTENSIONS = ['.md', '.markdown', '.txt'] as const
 export const SKIP_DIRS = new Set([