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/main.py

@@ -0,0 +1,41 @@
+"""FastAPI application entry point."""
+
+import logging
+from contextlib import asynccontextmanager
+
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.config import settings
+from app.routers import contact, equipment, health
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    """Manage application startup and shutdown."""
+    logger.info("HMS Licht & Ton API starting up...")
+    yield
+    logger.info("HMS Licht & Ton API shutting down...")
+
+
+app = FastAPI(
+    title="HMS Licht & Ton API",
+    description="Backend API for HMS Licht & Ton equipment rental platform.",
+    version="1.0.0",
+    lifespan=lifespan,
+)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=settings.cors_origins_list,
+    allow_methods=["GET", "POST"],
+    allow_headers=["*"],
+    allow_credentials=True,
+)
+
+app.include_router(health.router, prefix="/api")
+app.include_router(equipment.router, prefix="/api")
+app.include_router(contact.router, prefix="/api")