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/calendar-heatmap/calendar-heatmap.js

@@ -1,10 +1,39 @@
 const util = require('../../utils/util')
 
+/**
+ * Generate 4 heat color shades from a primary color.
+ * Returns colors from lightest to darkest.
+ */
+const generateHeatColors = (hex) => {
+  if (!hex || hex.charAt(0) !== '#') {
+    return ['#FFE0D0', '#FFB088', '#FF6B35', '#E05520']
+  }
+  const r = parseInt(hex.slice(1, 3), 16)
+  const g = parseInt(hex.slice(3, 5), 16)
+  const b = parseInt(hex.slice(5, 7), 16)
+
+  return [
+    `rgba(${r},${g},${b},0.15)`,  // lightest
+    `rgba(${r},${g},${b},0.35)`,  // light
+    `rgba(${r},${g},${b},0.65)`,  // medium
+    `rgba(${r},${g},${b},0.95)`   // darkest
+  ]
+}
+
+const getHeatColor = (duration, colors) => {
+  if (!duration || duration <= 0) return 'transparent'
+  if (duration < 30) return colors[0]
+  if (duration < 60) return colors[1]
+  if (duration < 120) return colors[2]
+  return colors[3]
+}
+
 Component({
   properties: {
     year: { type: Number, value: new Date().getFullYear() },
     month: { type: Number, value: new Date().getMonth() + 1 },
-    records: { type: Array, value: [] }
+    records: { type: Array, value: [] },
+    primaryColor: { type: String, value: '#FF6B35' }
   },
 
   data: {
@@ -12,20 +41,20 @@ Component({
   },
 
   observers: {
-    'year, month, records'(year, month, records) {
-      this._compute(year, month, records)
+    'year, month, records, primaryColor'(year, month, records, primaryColor) {
+      this._compute(year, month, records, primaryColor)
     }
   },
 
   lifetimes: {
     ready() {
-      const { year, month, records } = this.properties
-      this._compute(year, month, records)
+      const { year, month, records, primaryColor } = this.properties
+      this._compute(year, month, records, primaryColor)
     }
   },
 
   methods: {
-    _compute(year, month, records) {
+    _compute(year, month, records, primaryColor) {
       const weeks = util.getMonthCalendar(year, month)
       const recordMap = {}
       if (records && records.length) {
@@ -35,18 +64,13 @@ Component({
         })
       }
 
+      const heatColors = generateHeatColors(primaryColor || '#FF6B35')
+
       const data = weeks.map((week) =>
         week.map((day) => {
           if (!day) return null
           const duration = recordMap[day] || 0
-          let color = 'transparent'
-          if (duration > 0) {
-            if (duration < 30) color = '#FFE0D0'
-            else if (duration < 60) color = '#FFB088'
-            else if (duration < 120) color = '#FF6B35'
-            else color = '#E05520'
-          }
-          return { day, duration, color }
+          return { day, duration, color: getHeatColor(duration, heatColors) }
         })
       )
 
@@ -64,15 +88,6 @@ Component({
         day,
         duration: cell.duration
       })
-    },
-
-    getHeatColor(cell) {
-      if (!cell || cell.duration <= 0) return 'transparent'
-      const d = cell.duration
-      if (d < 30) return '#FFE0D0'
-      if (d < 60) return '#FFB088'
-      if (d < 120) return '#FF6B35'
-      return '#E05520'
     }
   }
 })