feat(ui): first-login onboarding tour — 4-step spotlight highlight, skip/prev/next/finish, replay from settings (v1.20 A)

[argszero]

Summary

UI/UE 5th-round deepening — item A: first-login onboarding tour (rant 2026-08-17T20:46:57, v1.20).

On first login (no localStorage atp-tour-done), a lightweight 4-step tour guides the new user, spotlight-highlighting each area in order:

1. 仪表盘 (#dash-stats) — balance / trends
2. 模型市场 (#view-marketplace) — browse / use models
3. 共享管理 (#view-sharing) — list idle keys to earn points
4. 钱包 / 设置 (#endpoint-card) — top-up, API Key, endpoint Base URLs

Implementation — non-modal floating layer:

• #tour-overlay: semi-dim backdrop (click = close)
• #tour-ring: accent outline highlight ring positioned via getBoundingClientRect, tour-pulse breathing animation (static under prefers-reduced-motion)
• #tour-pop: tooltip card — top-right 「跳过」, bottom 「上一步 / 下一步 / 完成」(becomes 完成 on last step), step counter n / 4 (data-tour-action delegation)
• Steps auto-switch views (switchView(view, {sync:false}) — no history pollution); popup clamped to viewport
• Esc / outside click / skip / finish all close, and closing writes atp-tour-done=1 (never shown again)
• Settings page gets a 「重新查看引导」 replay button (#tour-replay-btn → startTour())

Esc priority: tour open → Esc closes tour first (before help panel / inline forms).

Docs: docs/user-stories.md v1.20 + ui/README.md「首次引导 tour 约定」. Verified by DOM-stub smoke test (27 assertions: trigger on first login, step content/counter, view auto-switch, ring positioning, finish→done, no re-trigger, skip/outside/Esc close + mark, prev boundary, replay button, CSS incl. reduced-motion), cargo test, cargo fmt --check.

Rant (verbatim)

Rant: UI/UE 第五轮多角度深化 — 首次引导、复制后续引导、密度切换、最近使用、CSV 导出、表格键盘导航、品牌氛围（宿主 2026-08-17 第五轮指示：继续从多角度美化 UI、优化 UE）

A. 新用户首次引导（onboarding tour）

• 首次登录（localStorage 标记 atp_tour_done，无则触发）显示轻量引导浮层：4-5 步依次高亮
  ① 仪表盘（看余额/趋势）→ ② 模型市场（浏览/使用模型）→ ③ 共享管理（上架 key 赚点数）→ ④ 钱包/设置（充值、API Key、接入端点）
• 实现：非 modal 浮层 + 目标元素 accent 描边高亮（outline 动画），右上角「跳过」、底部「上一步/下一步/完成」
• Esc 或点浮层外可关闭；关闭后标记 done，不再出现（设置页可加「重新查看引导」入口）

Related

• Rant timestamp: 2026-08-17T20:46:57.465428 (project aitokenpool, status in_progress; items B–G to follow)
• Branch: feat/ui-ue-round5-onboarding (per rant: 分支 feat/ui-ue-round5)

Tests

• DOM-stub smoke test — 27/27 assertions pass
• node --check ui/js/app.js
• cargo test — 1 passed
• cargo fmt --check