docs(uiux): UIUX 设计方案大改 + 5 份作业指导书对齐 + 开发任务文档

- UIUX 文档：填充 19 个缺口（多主体画像/健康度/AI+看板/增长域/洞察域/创始人端/OODA/助推/商密）
- UIUX 文档：插入 6 个新章节（十四~十九），旧章节重编号为二十~三十一，更新目录和交叉引用
- 作业指导书 x5：导航改为 6 域分组，新增 Context Bar/工作模式/Insight Rail/决策线程/多工作区等 UI 概念
- 新建 docs/2-task-uiux.md：50 个代码落地开发任务，按 P0-P6 分优先级 + 8 Sprint 规划
- 后端/前端：大量新增模型、路由、组件（来自之前 Phase 开发）

backend/app/routers/nudges.py

@@ -0,0 +1,42 @@
+"""行为助推路由。"""
+
+from fastapi import APIRouter, Depends, Query
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.core.database import get_db
+from app.core.dependencies import get_current_user
+from app.models.nudge import NudgeRecord
+from app.models.user import User
+from app.schemas.common import ApiResponse, success
+from app.services.nudge_agent import select_nudge_strategy
+
+router = APIRouter(prefix="/nudges", tags=["nudges"])
+
+
+@router.get("", response_model=ApiResponse[list])
+async def list_nudges(company_id: str | None = Query(default=None), db: AsyncSession = Depends(get_db), user: User = Depends(get_current_user)):
+    """获取助推记录列表。"""
+    query = select(NudgeRecord)
+    if company_id:
+        query = query.where(NudgeRecord.company_id == company_id)
+    result = await db.execute(query.order_by(NudgeRecord.created_at.desc()))
+    items = result.scalars().all()
+    return success(data=[
+        {
+            "id": str(i.id),
+            "company_id": str(i.company_id),
+            "nudge_type": i.nudge_type,
+            "message": i.message,
+            "accepted": i.accepted,
+            "effect_result": i.effect_result,
+        }
+        for i in items
+    ])
+
+
+@router.post("/select", response_model=ApiResponse[dict])
+async def select_nudge(req: dict, user: User = Depends(get_current_user)):
+    """AI 选择助推策略。"""
+    result = await select_nudge_strategy(req.get("context", ""))
+    return success(data=result)