refactor(i18n): 移除 chrome.i18n 国际化，统一使用中文硬编码

移除 chromeI18n 工具、_locales 翻译文件和 manifest default_locale 配置，
将所有 UI 文案改为直接硬编码中文，并更新相关测试与文档。

src/components/__tests__/TextInputArea.test.tsx

@@ -18,12 +18,12 @@ describe('TextInputArea 组件', () => {
 
     it('默认显示清空按钮', () => {
       render(<TextInputArea value="有内容" onChange={() => {}} />);
-      expect(screen.getByRole('button', { name: 'textInputArea.clear' })).toBeInTheDocument();
+      expect(screen.getByRole('button', { name: '清空' })).toBeInTheDocument();
     });
 
     it('无内容时清空按钮应隐藏', () => {
       render(<TextInputArea value="" onChange={() => {}} />);
-      expect(screen.queryByRole('button', { name: 'textInputArea.clear' })).not.toBeInTheDocument();
+      expect(screen.queryByRole('button', { name: '清空' })).not.toBeInTheDocument();
     });
 
     it('disabled 时清空按钮应隐藏', () => {
@@ -57,7 +57,7 @@ describe('TextInputArea 组件', () => {
       const handleChange = vi.fn();
       render(<TextInputArea value="内容" onChange={handleChange} />);
 
-      fireEvent.click(screen.getByRole('button', { name: 'textInputArea.clear' }));
+      fireEvent.click(screen.getByRole('button', { name: '清空' }));
 
       expect(handleChange).toHaveBeenCalledWith('');
     });
@@ -81,7 +81,7 @@ describe('TextInputArea 组件', () => {
     it('清空按钮应清空内容', () => {
       render(<TextInputArea defaultValue="内容" />);
 
-      fireEvent.click(screen.getByRole('button', { name: 'textInputArea.clear' }));
+      fireEvent.click(screen.getByRole('button', { name: '清空' }));
 
       expect(screen.getByRole('textbox')).toHaveValue('');
     });
@@ -90,14 +90,12 @@ describe('TextInputArea 组件', () => {
   describe('allowCopy 复制功能', () => {
     it('allowCopy 且有内容时显示复制按钮', () => {
       render(<TextInputArea value="可复制的内容" onChange={() => {}} allowCopy />);
-      expect(screen.getByRole('button', { name: 'textInputArea.copyContent' })).toBeInTheDocument();
+      expect(screen.getByRole('button', { name: '复制内容' })).toBeInTheDocument();
     });
 
     it('allowCopy 但无内容时隐藏复制按钮', () => {
       render(<TextInputArea value="" onChange={() => {}} allowCopy />);
-      expect(
-        screen.queryByRole('button', { name: 'textInputArea.copyContent' }),
-      ).not.toBeInTheDocument();
+      expect(screen.queryByRole('button', { name: '复制内容' })).not.toBeInTheDocument();
     });
 
     it('allowCopy=false 时不显示复制按钮', () => {
@@ -113,7 +111,7 @@ describe('TextInputArea 组件', () => {
 
       render(<TextInputArea value="测试" onChange={() => {}} allowCopy />);
 
-      await user.click(screen.getByRole('button', { name: 'textInputArea.copyContent' }));
+      await user.click(screen.getByRole('button', { name: '复制内容' }));
 
       expect(writeTextSpy).toHaveBeenCalledWith('测试');
     });
@@ -126,7 +124,7 @@ describe('TextInputArea 组件', () => {
 
       render(<TextInputArea value="测试" onChange={() => {}} allowCopy />);
 
-      await user.click(screen.getByRole('button', { name: 'textInputArea.copyContent' }));
+      await user.click(screen.getByRole('button', { name: '复制内容' }));
 
       expect(writeTextSpy).toHaveBeenCalledWith('测试');
     });
@@ -158,6 +156,7 @@ describe('TextInputArea 组件', () => {
       fireEvent.change(textarea, { target: { value: '123456' } });
 
       expect(handleChange).not.toHaveBeenCalledWith('123456');
+      expect(screen.getByText('内容不能超过 5 个字符')).toBeInTheDocument();
     });
 
     it('未超出 maxLength 的输入应正常触发', () => {
@@ -370,7 +369,7 @@ describe('TextInputArea 组件', () => {
       const writeTextSpy = vi.spyOn(navigator.clipboard, 'writeText').mockResolvedValue(undefined);
 
       render(<TextInputArea value="测试" onChange={() => {}} allowCopy />);
-      await user.click(screen.getByRole('button', { name: 'textInputArea.copyContent' }));
+      await user.click(screen.getByRole('button', { name: '复制内容' }));
 
       expect(writeTextSpy).toHaveBeenCalledWith('测试');
     });
@@ -381,7 +380,7 @@ describe('TextInputArea 组件', () => {
       const handleClear = vi.fn();
       render(<TextInputArea value="内容" onChange={() => {}} onClear={handleClear} />);
 
-      fireEvent.click(screen.getByRole('button', { name: 'textInputArea.clear' }));
+      fireEvent.click(screen.getByRole('button', { name: '清空' }));
 
       expect(handleClear).toHaveBeenCalledOnce();
     });
@@ -389,7 +388,7 @@ describe('TextInputArea 组件', () => {
     it('不传 onClear 时清空按钮应正常工作', () => {
       render(<TextInputArea defaultValue="内容" />);
 
-      fireEvent.click(screen.getByRole('button', { name: 'textInputArea.clear' }));
+      fireEvent.click(screen.getByRole('button', { name: '清空' }));
 
       expect(screen.getByRole('textbox')).toHaveValue('');
     });