feat(project): initialize ZUGFeRD service with pyproject.toml and directory structure

pyproject.toml

@@ -0,0 +1,35 @@
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "zugferd-service"
+version = "1.0.0"
+description = "REST API for ZUGFeRD invoice extraction and validation"
+requires-python = ">=3.11"
+dependencies = [
+    "fastapi>=0.109.0",
+    "uvicorn>=0.27.0",
+    "python-multipart>=0.0.6",
+    "factur-x>=2.5",
+    "pypdf>=4.0.0",
+    "pydantic>=2.5.0",
+    "lxml>=5.0.0",
+]
+
+[project.optional-dependencies]
+dev = [
+    "pytest>=8.0.0",
+    "pytest-asyncio>=0.23.0",
+    "httpx>=0.27.0",
+]
+
+[project.scripts]
+zugferd-service = "src.main:run"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src"]
+
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+testpaths = ["tests"]