chore: initial project scaffold and gitignore

app/main.py

@@ -0,0 +1,35 @@
+"""FastAPI application entrypoint."""
+
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.health import router as health_router
+from app.api.portfolios import router as portfolio_router
+from app.core.config import get_settings
+from app.core.errors import register_exception_handlers
+
+
+def create_app() -> FastAPI:
+    settings = get_settings()
+    app = FastAPI(
+        title=settings.app_name,
+        version=settings.app_version,
+        docs_url="/docs",
+        redoc_url="/redoc",
+    )
+
+    app.add_middleware(
+        CORSMiddleware,
+        allow_origins=settings.allowed_origins,
+        allow_credentials=True,
+        allow_methods=["GET", "POST", "PATCH", "DELETE", "OPTIONS"],
+        allow_headers=["Authorization", "Content-Type"],
+    )
+
+    app.include_router(health_router)
+    app.include_router(portfolio_router)
+    register_exception_handlers(app)
+    return app
+
+
+app = create_app()