feat: scaffold backend with FastAPI, config files, and health endpoint

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/main.py

@@ -0,0 +1,25 @@
+from contextlib import asynccontextmanager
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    # Startup
+    yield
+    # Shutdown
+
+
+app = FastAPI(title="TV Dashboard API", lifespan=lifespan)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+
+@app.get("/api/health")
+async def health():
+    return {"status": "ok"}