fix(ui+permission): 移除联合投稿 / emoji换SVG / 修复移动端浅色适配 / 已排期显示日期 / 隐藏.env提示 / 公开排期档期游客访问

具体改动：

1. feat(投稿表单): 移除 RequestForm.vue 联合投稿功能整套模板+状态+payload+CSS(10处残留)

2. feat(图标): Icon.vue 新增 sparkles/star 图标; 首页档期卡片📅🎵✨和排期列表空状态🎵📅换成 lucide SVG Icon

3. fix(浅色适配): ScheduleList.vue 日期选择弹窗桌面端+移动端(content/header/h3/close-btn/item)全部改为 bg-primary + var text + indigo 主色, 修复竖屏选择日期标题白字看不见

4. feat(歌曲列表): SongList.vue scheduled-tag 内联追加 formatScheduleDate, 徽章+日期双胶囊显示

5. fix(登录): OAuthButtons.vue showPlaceholderHint 强制 false, 隐藏虚线框 .env 配置提示

6. fix(权限): server/middleware/auth.ts + auth-route-policy.ts 双白名单同步追加 /api/expected-play-dates GET 公共访问, 修复未登录 Authentication expired 401

app/components/Songs/SongList.vue

@@ -234,14 +234,16 @@
                   </span>
                   <span
                     v-else-if="song.scheduled"
-                    :title="
-                      song.scheduleDate
-                        ? `排期日期：${formatScheduleDate(song.scheduleDate)}`
-                        : '已排期'
-                    "
-                    class="scheduled-tag"
+                    class="scheduled-group"
                   >
-                    已排期
+                    <span class="scheduled-tag">已排期</span>
+                    <span
+                      v-if="song.scheduleDate"
+                      :title="`排期日期：${formatScheduleDate(song.scheduleDate)}`"
+                      class="scheduled-date"
+                    >
+                      {{ formatScheduleDate(song.scheduleDate) }}
+                    </span>
                   </span>
                   <span v-else-if="song.isReplay" title="重播歌曲" class="replay-tag"> 重播 </span>
                   <button
@@ -2268,17 +2270,36 @@ const vRipple = {
   transform: scale(1.2);
 }
 
+.scheduled-group {
+  display: inline-flex;
+  align-items: center;
+  gap: 0.35rem;
+  margin-left: 0.5rem;
+  flex-shrink: 0;
+  align-self: center;
+}
+
 .scheduled-tag {
   display: inline-flex;
-  background: rgba(16, 185, 129, 0.2);
-  border: 1px solid rgba(16, 185, 129, 0.4);
-  border-radius: 4px;
-  padding: 0.15rem 0.4rem;
-  font-size: 0.7rem;
-  color: #10b981;
-  margin-left: 0.5rem;
-  flex-shrink: 0; /* 防止标签被压缩 */
-  align-self: center; /* 确保垂直居中 */
+  background: rgba(16, 185, 129, 0.12);
+  border: 1px solid rgba(16, 185, 129, 0.35);
+  border-radius: 6px;
+  padding: 0.15rem 0.5rem;
+  font-size: 0.72rem;
+  font-weight: 700;
+  color: #059669;
+}
+
+.scheduled-date {
+  display: inline-flex;
+  align-items: center;
+  font-size: 0.72rem;
+  font-weight: 600;
+  color: var(--text-secondary, #52525b);
+  background: var(--bg-secondary, #f4f4f5);
+  padding: 0.15rem 0.5rem;
+  border-radius: 6px;
+  border: 1px solid var(--border-secondary, #e4e4e7);
 }
 
 .played-tag {