@

docs: reorganize api docs into categorized subdirectories and fill missing docs

- Categorize 77 existing api docs into 16 business-domain subdirectories
  (auth/ad/wallet/coupon/compare/savings/signin/tasks/invite/user/
   device/platform/intent/meituan/other) plus admin/ and internal/
- Split admin/ into 7 sub-resource subdirectories (auth/users/wallet/
  withdraws/feedbacks/admins/ad) with 4 single-file docs at root
- Create 21 new docs covering 28 previously undocumented endpoints:
  ad/watch-report, wallet/transfer-auth (3 endpoints), coupon/session+
  stats+completed-today+prompt (7), invite/me+invitees+bind+landing-track,
  user/onboarding (2), platform/flags+ad-config+app-version,
  intent/step+precoupon/step, analytics/events, order/report,
  report/submit+records, feedback/config+records, trace/finalize
- Add mock request/response JSON examples to all new docs
- Create docs/README.md with full category index for LLM navigation
- Update docs/api/README.md: fix all links, add new endpoint rows,
  replace "no doc" markers with actual links
- Fix back-navigation links (./README.md -> ../README.md or
  ../../README.md) in all moved files
@

docs/api/auth/auth-sms-send.md

@@ -0,0 +1,26 @@
+# POST /api/v1/auth/sms/send — 发送短信验证码
+
+> 所属:Auth 组（前缀 `/api/v1/auth`） | 鉴权:无 | [← 返回 API 索引](../README.md)
+>
+> 集成实现:见 [integrations/sms](../integrations/sms.md)（mock 模式、频控、接真供应商 TODO）。
+
+## 入参
+
+| 字段 | 类型 | 必填 | 说明 |
+|---|---|---|---|
+| `phone` | string | ✅ | 手机号,正则 `^1\d{10}$` |
+
+## 出参
+响应 `200`:
+
+| 字段 | 类型 | 说明 |
+|---|---|---|
+| `sent` | bool | 是否已发送 |
+| `mock` | bool | 是否 mock 模式（true 时不真发,任意 6 位通过） |
+| `cooldown_sec` | int | 多少秒后才能再次发送 |
+
+## 错误码
+- `429` 发送过频（默认 60s 冷却内重复发）
+
+## 说明
+mock 模式（`SMS_MOCK=true`）下不真发短信,仅记录冷却时间。