feat: Kinetic Dark 设计语言 + Lucide 图标迁移 + 首页轻量个性化

- 建立 Lucide 子集 iconfont（49 字形），全站 emoji 替换为 fc-icon 组件
- 重塑 Design Token（冷中性近黑底 + Volt 荧光绿 #B6F24E），消除硬编码颜色
- 首页登录后个性化：我的计划 / 我的收藏 / 今日推荐（纯前端复用现有 API）
- 后端 DEFAULT_EMOJI→Lucide 名，PALETTE 对齐 Kinetic Dark 语义色板
- 修复 person-standing 缺失字形；14 个官方组合 seed emoji 全部映射到现有字形

miniprogram/utils/icon-map.js

@@ -0,0 +1,53 @@
+// AUTO-GENERATED by /tmp/gen_iconfont.mjs — 勿手改
+// Lucide (MIT) 子集 iconfont，font-family: fc-icon
+module.exports = {
+  "zap": "\\uf101",
+  "x-circle": "\\uf102",
+  "user": "\\uf103",
+  "trophy": "\\uf104",
+  "trending-up": "\\uf105",
+  "trash-2": "\\uf106",
+  "target": "\\uf107",
+  "star": "\\uf108",
+  "sparkles": "\\uf109",
+  "sliders-horizontal": "\\uf10a",
+  "share-2": "\\uf10b",
+  "settings": "\\uf10c",
+  "search": "\\uf10d",
+  "rotate-cw": "\\uf10e",
+  "refresh-cw": "\\uf10f",
+  "plus": "\\uf110",
+  "play": "\\uf111",
+  "person-standing": "\\uf112",
+  "medal": "\\uf113",
+  "log-out": "\\uf114",
+  "layout-grid": "\\uf115",
+  "layers": "\\uf116",
+  "info": "\\uf117",
+  "image": "\\uf118",
+  "home": "\\uf119",
+  "heart": "\\uf11a",
+  "grid-2x2": "\\uf11b",
+  "folder-open": "\\uf11c",
+  "flame": "\\uf11d",
+  "filter": "\\uf11e",
+  "dumbbell": "\\uf11f",
+  "download": "\\uf120",
+  "clock": "\\uf121",
+  "clipboard-list": "\\uf122",
+  "circle-x": "\\uf123",
+  "chevron-right": "\\uf124",
+  "chevron-down": "\\uf125",
+  "check": "\\uf126",
+  "check-circle": "\\uf127",
+  "calendar": "\\uf128",
+  "bookmark": "\\uf129",
+  "bike": "\\uf12a",
+  "bell": "\\uf12b",
+  "award": "\\uf12c",
+  "arrow-right": "\\uf12d",
+  "arrow-left": "\\uf12e",
+  "alert-circle": "\\uf12f",
+  "activity": "\\uf130",
+  "accessibility": "\\uf131"
+};