Develop (#55)

feat: optimize dashboard/search UX and simplify extension architecture

Redesign Dashboard with compact tool grid and recently used tools
Improve TopBar search UX with Cmd/Ctrl+K shortcut and better history navigation
Reorganize project structure into src/
Migrate i18n from react-i18next to chrome.i18n
Remove runtime language switch and settings page
Remove HTML/Markdown conversion tools
Clean up unused code, dead animations, redundant comments, and imports
Improve component consistency with shadcn/ui patterns
Replace hardcoded strings/colors with i18n tokens and theme tokens
Add comprehensive project documentation and coding standards
Fix CI artifact upload workflow and multiple TypeScript/test issues

Includes various refactors, UI polish, i18n cleanup, CI improvements,
and maintenance updates across the codebase.

src/utils/clipboard.ts

@@ -0,0 +1,31 @@
+/**
+ * 复制文本到剪贴板
+ * @param text 要复制的文本
+ * @returns Promise<boolean> 是否复制成功
+ */
+export async function copyTextToClipboard(text: string): Promise<boolean> {
+  try {
+    await navigator.clipboard.writeText(text);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+/**
+ * 复制图片到剪贴板
+ * @param blob 要复制的图片
+ * @returns Promise<boolean> 是否复制成功
+ */
+export async function copyImageToClipboard(blob: Blob): Promise<boolean> {
+  try {
+    await navigator.clipboard.write([
+      new ClipboardItem({
+        'image/png': blob,
+      }),
+    ]);
+    return true;
+  } catch {
+    return false;
+  }
+}