feat(backend): Phase 0 项目骨架完成 — 后端/前端/数据库/Docker

- 后端：FastAPI + SQLAlchemy + Alembic，7 张核心表迁移成功
- 前端：Next.js 16 + TailwindCSS 4 + 三端布局（投资人/创始人/Admin）
- 数据库：PostgreSQL 16，7 张核心实体表（tenants/users/companies/monthly_reports/health_scores/risk_events/audit_logs）
- Docker：docker-compose.yml + 前后端 Dockerfile
- 测试：健康检查 4 个测试全部 GREEN
- 文档：README/run.md/AGENTS.md/docs 体系完整

backend/app/models/health_score.py

@@ -0,0 +1,33 @@
+"""健康度评分模型。
+
+多维度评分：财务、经营、AI+ 商业化、AI+ 成本。
+"""
+
+import uuid
+from datetime import datetime, timezone
+
+from sqlalchemy import DateTime, Float, ForeignKey, String
+from sqlalchemy.dialects.postgresql import JSONB
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.database import Base
+
+
+class HealthScore(Base):
+    """健康度评分。"""
+
+    __tablename__ = "health_scores"
+
+    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
+    company_id: Mapped[str] = mapped_column(String(36), ForeignKey("companies.id"), nullable=False, index=True)
+    total_score: Mapped[float] = mapped_column(Float, nullable=False, comment="总分（0-100）")
+    financial_score: Mapped[float | None] = mapped_column(Float, nullable=True, comment="财务健康度")
+    operational_score: Mapped[float | None] = mapped_column(Float, nullable=True, comment="经营健康度")
+    ai_commercial_score: Mapped[float | None] = mapped_column(Float, nullable=True, comment="AI+ 商业化健康度")
+    ai_cost_score: Mapped[float | None] = mapped_column(Float, nullable=True, comment="AI+ 成本健康度")
+    trend: Mapped[str | None] = mapped_column(String(20), nullable=True, comment="趋势：up/stable/down")
+    evidence_json: Mapped[dict | None] = mapped_column(JSONB, nullable=True, comment="评分依据")
+    recommendations_json: Mapped[dict | None] = mapped_column(JSONB, nullable=True, comment="建议动作")
+    calculated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), default=lambda: datetime.now(timezone.utc)
+    )