feat(backend): FastAPI endpoint with NDJSON streaming and CORS for Vite frontend

backend/pyproject.toml

@@ -10,12 +10,16 @@ requires-python = ">=3.11"
 dependencies = [
     "pydantic>=2.6,<3",
     "click>=8.1,<9",
+    "fastapi>=0.110,<1",
+    "uvicorn[standard]>=0.27,<1",
+    "python-multipart>=0.0.9,<1",
 ]
 
 [project.optional-dependencies]
 dev = [
     "pytest>=8.0",
     "pytest-cov>=4.1",
+    "httpx>=0.27,<1",
 ]
 
 [project.scripts]