feat: T03 backend core – FastAPI + DB models + Equipment API + Redis cache + health + tests

- FastAPI app with CORS, lifespan handlers
- Pydantic Settings config (DB, Redis, CORS, SMTP, JWT, Rentman)
- SQLAlchemy async engine + session (DeclarativeBase)
- 6 DB models: EquipmentCache, RentalRequest, RentalRequestItem, Contact, AdminUser, SyncLog
- Pydantic schemas: EquipmentItem, EquipmentDetail, PaginatedEquipment, ContactCreate, ContactResponse
- Redis cache helper: set/get/delete_pattern, rate limiting, equipment key builders
- Equipment router: list (search/category/sort/pagination), detail, categories – all cached
- Contact router: POST with Pydantic validation + rate limiting (5/min)
- Health router: GET /api/health with DB + Redis status
- 28 pytest tests (all pass, 90% coverage)
- Dockerfile, requirements.txt, pytest.ini, test_report.md

backend/app/models/equipment.py

@@ -0,0 +1,36 @@
+"""EquipmentCache SQLAlchemy model."""
+
+from datetime import datetime
+
+from sqlalchemy import JSON, Boolean, Index, Integer, Numeric, String, Text, func
+from sqlalchemy.dialects.postgresql import JSONB
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.database import Base
+
+
+class EquipmentCache(Base):
+    """Cached equipment data imported from Rentman."""
+
+    __tablename__ = "equipment_cache"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    rentman_id: Mapped[str] = mapped_column(String(64), unique=True, nullable=False, index=True)
+    name: Mapped[str] = mapped_column(String(255), nullable=False, index=True)
+    number: Mapped[str | None] = mapped_column(String(64), nullable=True, index=True)
+    category: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)
+    subcategory: Mapped[str | None] = mapped_column(String(128), nullable=True)
+    description: Mapped[str | None] = mapped_column(Text, nullable=True)
+    specifications: Mapped[dict | None] = mapped_column(JSON, nullable=True)
+    images: Mapped[list | None] = mapped_column(JSON, nullable=True)
+    rental_price: Mapped[float | None] = mapped_column(Numeric(10, 2), nullable=True)
+    brand: Mapped[str | None] = mapped_column(String(128), nullable=True)
+    available: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)
+    created_at: Mapped[datetime] = mapped_column(server_default=func.now(), nullable=False)
+    updated_at: Mapped[datetime] = mapped_column(server_default=func.now(), onupdate=func.now(), nullable=False)
+
+    __table_args__ = (
+        Index("idx_equipment_category", "category"),
+        Index("idx_equipment_name", "name"),
+        Index("idx_equipment_number", "number"),
+    )