feat: initial project setup

- FastAPI backend (Python 3.12, uv)
- React 19 + TypeScript + Vite frontend
- Devcontainer with Node 22, Python 3.12, uv, opencode
- Basic app structure and project docs

backend/.python-version

@@ -0,0 +1 @@
+3.12

backend/app/main.py

@@ -0,0 +1,22 @@
+from fastapi import FastAPI
+
+from .settings import settings
+
+app = FastAPI(
+    title="Kirche Einfach API",
+    description="KI-gestützte Verwaltungsplattform für Kirche",
+    version="0.1.0",
+    docs_url="/api/docs",
+    redoc_url="/api/redoc",
+    openapi_url="/api/openapi.json",
+)
+
+
+@app.get("/")
+async def root():
+    return {"message": "Kirche Einfach API", "version": settings.version}
+
+
+@app.get("/health")
+async def health():
+    return {"status": "ok"}

backend/app/settings.py

@@ -0,0 +1,11 @@
+from pydantic_settings import BaseSettings
+
+
+class Settings(BaseSettings):
+    version: str = "0.1.0"
+    debug: bool = False
+
+    model_config = {"env_prefix": "KIRCHE_"}
+
+
+settings = Settings()

backend/pyproject.toml

@@ -0,0 +1,19 @@
+[project]
+name = "kirche-einfach-backend"
+version = "0.1.0"
+description = "Kirche Einfach - KI-gestuetzte Verwaltungsplattform fuer Kirche"
+requires-python = ">=3.12"
+dependencies = [
+    "fastapi[standard]>=0.115.0",
+    "django>=5.1",
+    "pydantic-settings>=2.0",
+    "uvicorn[standard]>=0.30.0",
+]
+
+[build-system]
+requires = ["uv_build>=0.12.3,<0.13"]
+build-backend = "uv_build"
+
+[tool.uv.build-backend]
+module-name = "app"
+module-root = ""