feat:重构按钮和icon组件

miniprogram/englishPages/letterTracing/letterTracing.wxml

@@ -66,33 +66,30 @@
             </view>
         </view>
 
-        <button
+        <toy-button
             wx:if="{{showNextLetter}}"
-            hover-class="none"
-            class="lt-shuffle-btn"
-            bindtap="onNextLetter">
-            🔄 换一批
-        </button>
+            type="default"
+            variant="outlined"
+            block
+            icon="refresh"
+            custom-class="lt-shuffle-btn"
+            bind:click="onNextLetter">
+            换一批
+        </toy-button>
 
         <draw-ad type="mathDraw"></draw-ad>
         <view class="lt-spacer-bottom"></view>
     </view>
 </view>
 
-<view class="lt-bottom-bar">
-    <button class="lt-bottom-share" hover-class="none" open-type="share">
-        <text class="lt-bottom-icon">↗</text>
-        分享
-    </button>
-    <button
-        class="lt-bottom-save"
-        hover-class="none"
-        disabled="{{!hasContent}}"
-        bindtap="exportToPrint">
-        <text class="lt-bottom-icon">⬇</text>
-        保存到相册
-    </button>
-</view>
+<preview-footer-actions
+    primary-text="保存到相册"
+    primary-icon="download"
+    secondary-text="分享"
+    secondary-icon="wechat"
+    disabled="{{!hasContent}}"
+    bind:primary="exportToPrint"
+    bind:secondary="onShare" />
 
 <share-guide-popup
     show="{{showShareDialog}}"