fix(ui): 根治真机弹窗 fixed 降级(移出 .container + pageIn 去 transform)

根因:.page-enter 的 pageIn 动画含 transform,即使 to: transform:none,
真机 fill-mode 没真正消除 transform,.container 仍是 fixed 的包含块。
记录页内容超一屏时 mask 降级相对 .container(高>>视口),flex 居中把
弹窗放到 .container 中心(视口外),真机看不到(模拟器宽松所以正常)。

- records: 日历详情弹窗移出 .container.page-enter,fixed 相对视口;
  加 style themeStyle 拿暗黑变量
- app.wxss: pageIn keyframes 去掉 transform 只留 opacity 淡入,根治所有
  页面(settings 计划编辑器/timer 完成弹窗)的 fixed 降级
- calendar-heatmap: onDayTap 的 find 用 Number(day) 修真机 dataset
  字符串化导致 === 失败;移除诊断日志

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app.wxss

@@ -129,11 +129,12 @@ image {
 }
 
 @keyframes pageIn {
-  from { opacity: 0; transform: translateY(20rpx); }
-  /* `none` (not translateY(0)) so the finished animation leaves NO transform
-     on .container - any non-none transform creates a containing block that
-     demotes descendant position:fixed to relative-to-container, breaking
-     full-screen modals (day-detail / plan-editor / completion) once the
-     page scrolls past one viewport height. */
-  to   { opacity: 1; transform: none; }
+  /* Opacity-only: any transform (even translateY(0) held by animation
+     fill-mode) makes .container a containing block that demotes descendant
+     position:fixed to relative-to-container, breaking full-screen modals on
+     real devices once the page scrolls past one viewport. The prior
+     `to: transform: none` did NOT hold on real devices, so drop transform
+     from the keyframes entirely. Pages still get a fade-in. */
+  from { opacity: 0; }
+  to   { opacity: 1; }
 }