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)

pages/leaderboard/leaderboard.wxss

@@ -0,0 +1,176 @@
+.container {
+  padding: 0;
+  padding-bottom: calc(134rpx + env(safe-area-inset-bottom));
+  min-height: 100vh;
+  box-sizing: border-box;
+}
+
+/* Period tabs */
+.period-tabs {
+  display: flex;
+  background: #FFFFFF;
+  padding: 0 32rpx;
+  border-bottom: 1rpx solid var(--border);
+  position: sticky;
+  top: 0;
+  z-index: 10;
+}
+
+.period-tab {
+  flex: 1;
+  text-align: center;
+  padding: 24rpx 0 20rpx;
+  font-size: 30rpx;
+  color: var(--text-secondary);
+  position: relative;
+  transition: color 0.2s;
+}
+
+.period-tab.active {
+  color: var(--primary);
+  font-weight: 600;
+}
+
+.period-tab.active::after {
+  content: '';
+  position: absolute;
+  bottom: 0;
+  left: 50%;
+  transform: translateX(-50%);
+  width: 40rpx;
+  height: 6rpx;
+  border-radius: 3rpx;
+  background: var(--primary);
+}
+
+/* Status */
+.status-wrap {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  padding-top: 120rpx;
+}
+
+.status-text {
+  font-size: 28rpx;
+  color: var(--text-secondary);
+}
+
+.empty-icon {
+  width: 120rpx;
+  height: 120rpx;
+  opacity: 0.3;
+  margin-bottom: 24rpx;
+}
+
+.empty-text {
+  font-size: 30rpx;
+  color: var(--text-secondary);
+  margin-bottom: 8rpx;
+}
+
+.empty-sub {
+  font-size: 26rpx;
+  color: var(--text-secondary);
+  opacity: 0.6;
+}
+
+/* Rank list */
+.rank-list {
+  padding: 16rpx 24rpx;
+}
+
+.rank-item {
+  display: flex;
+  align-items: center;
+  background: var(--card-bg);
+  border-radius: 16rpx;
+  padding: 20rpx 24rpx;
+  margin-bottom: 12rpx;
+  box-shadow: 0 2rpx 8rpx rgba(0, 0, 0, 0.04);
+}
+
+.rank-item.is-me {
+  background: var(--primary-bg);
+  border: 2rpx solid var(--primary);
+}
+
+/* Rank number */
+.rank-num {
+  width: 56rpx;
+  height: 56rpx;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 28rpx;
+  font-weight: 700;
+  color: var(--text-secondary);
+  border-radius: 50%;
+  background: #F5F5F5;
+  flex-shrink: 0;
+  margin-right: 16rpx;
+}
+
+.rank-num.gold   { background: #FFF7E6; color: #FA8C16; font-size: 36rpx; }
+.rank-num.silver { background: #F0F0F0; color: #8C8C8C; font-size: 36rpx; }
+.rank-num.bronze { background: #FFF1E6; color: #D46B08; font-size: 36rpx; }
+
+.rank-avatar {
+  width: 64rpx;
+  height: 64rpx;
+  border-radius: 50%;
+  background: #F0F0F0;
+  flex-shrink: 0;
+  margin-right: 16rpx;
+  opacity: 0.6;
+}
+
+.rank-info {
+  flex: 1;
+  min-width: 0;
+}
+
+.rank-name {
+  font-size: 28rpx;
+  font-weight: 500;
+  color: var(--text);
+  display: block;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.rank-sessions {
+  font-size: 22rpx;
+  color: var(--text-secondary);
+  margin-top: 4rpx;
+}
+
+.rank-dur {
+  font-size: 30rpx;
+  font-weight: 700;
+  color: var(--primary);
+  flex-shrink: 0;
+  margin-left: 16rpx;
+}
+
+/* My rank bar (pinned) */
+.my-bar {
+  position: fixed;
+  bottom: calc(110rpx + env(safe-area-inset-bottom));
+  left: 24rpx;
+  right: 24rpx;
+  display: flex;
+  align-items: center;
+  background: var(--primary-bg);
+  border: 2rpx solid var(--primary);
+  border-radius: 16rpx;
+  padding: 16rpx 24rpx;
+  z-index: 10;
+  box-shadow: 0 -4rpx 16rpx rgba(0, 0, 0, 0.08);
+}
+
+.my-bar .rank-name {
+  color: var(--primary);
+  font-weight: 600;
+}