style(auth): simplify resend button to text link style

apps/lib/features/auth/ui/screens/register_verification_screen.dart

@@ -260,32 +260,28 @@ class _RegisterVerificationViewState extends State<RegisterVerificationView> {
   }
 
   Widget _buildResendButton(bool canResend, RegisterState state) {
-    final borderColor = canResend ? AppColors.primary : AppColors.slate300;
     final textColor = canResend ? AppColors.primary : AppColors.slate400;
 
     String text;
     if (state.status == FormzSubmissionStatus.inProgress) {
-      text = '发送中...';
+      text = '发送中';
     } else if (canResend) {
-      text = '重新发送';
+      text = '重发';
     } else {
-      text = '$_countdown s';
+      text = '${_countdown}s';
     }
 
-    return SizedBox(
-      width: 90,
+    return GestureDetector(
+      onTap: canResend ? _handleResendCode : null,
+      behavior: HitTestBehavior.opaque,
+      child: Container(
         height: 40,
-      child: OutlinedButton(
-        onPressed: canResend ? _handleResendCode : null,
-        style: OutlinedButton.styleFrom(
-          backgroundColor: AppColors.background,
-          side: BorderSide(color: borderColor),
-          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
-        ),
+        padding: const EdgeInsets.symmetric(horizontal: 12),
+        alignment: Alignment.center,
         child: Text(
           text,
           style: TextStyle(
-            fontSize: 13,
+            fontSize: 14,
             fontWeight: FontWeight.w500,
             color: textColor,
           ),