feat: v1.5 — plan editor, voice prompts, UI polish

Major features:
- Training plan editor: edit preset days/duration per plan (in-place
  override via custom_plans storage; preset ids preserved so existing
  records stay valid)
- Voice prompts at 4 fixed points during training (halfway / 30s /
  10s / done) via Tencent Cloud TTS (cloudfunctions/tts + utils/voice.js)
- Free-training button: switched from outline (transparent) to ghost
  variant (theme-tinted) for visual weight

Bug fixes:
- 4 functional pages: SVG data URIs failed to render in WeChat because
  '\#' in colors was parsed as a data-URI fragment delimiter. encode the
  whole SVG via encodeURIComponent in utils/icons.js build().
- Old records (saved before id field was added) could not be deleted
  (data-id was empty, triggered defensive guard). Backfill stable
  legacy-<month>-<index>-<duration> ids in getRecords() and persist.
- settings.js plan-row editor button event was bubbling up to the row's
  bindtap (which also fired onSelectPlan). Wrapped in catch:tap.

UI:
- Settings page: 3 hardcoded plans replaced with dynamic buildPlansList
  that overlays custom_plans on top of presets
- Plan editor: bottom-sheet modal in settings page (regular view, not
  ui-modal — WeChat custom component root element drops position:fixed
  in this runtime)
- Free-training button: rounded pill style, full-width, 24rpx gap from
  primary action; bottom sheet uses max-height: 88vh + internal scroll
- Version bumped to v1.5, last updated 2026-06-10

Removed:
- Daily reminder section (dailyReminder / reminderTime) — replaced by
  the 4 voice prompts which cover the same user need without requiring
  long-term scheduling that WeChat mini-programs can't actually do

Misc:
- utils/plan.js refactored to formula-driven: presets declare
  totalDays/startTarget/increment/cycleDays, days[] is generated. Same
  formula applies to custom plans.
- Timer _remind() guards each prompt on minimum duration so short
  free-mode sessions don't fire 'last30' at the start
- Cloud storage cloud_plans field added to data push payload; restored
  on first install via _restoreFromCloud
- .gitignore added for local AI tool caches (.reasonix/, reasonix.toml,
  .codegraph/daemon.pid)

components/ui-card/ui-card.wxss

@@ -0,0 +1,34 @@
+.ui-card {
+  background: var(--card-bg, #FFFFFF);
+  border-radius: 24rpx;
+  padding: 32rpx;
+  margin-bottom: 24rpx;
+  box-shadow: 0 2rpx 16rpx rgba(0, 0, 0, 0.06);
+  box-sizing: border-box;
+}
+
+.ui-card--flush {
+  padding: 0;
+}
+
+/* Soft variant: subtle background tint, no shadow */
+.ui-card.soft {
+  background: rgba(var(--primary-rgb, 255, 107, 53), 0.04);
+  box-shadow: none;
+  border-radius: 20rpx;
+}
+
+/* Staggered entrance animation */
+.ui-card.in {
+  animation: uiCardIn 0.45s ease both;
+}
+
+.ui-card.in:nth-child(1) { animation-delay: 0.05s; }
+.ui-card.in:nth-child(2) { animation-delay: 0.15s; }
+.ui-card.in:nth-child(3) { animation-delay: 0.25s; }
+.ui-card.in:nth-child(4) { animation-delay: 0.35s; }
+
+@keyframes uiCardIn {
+  from { opacity: 0; transform: translateY(40rpx); }
+  to   { opacity: 1; transform: translateY(0); }
+}