feat: Add Booklooker client configuration and exception handling

- Introduced BooklookerConfig class for runtime configuration management.
- Created custom exceptions for API errors, including authentication and validation errors.
- Generated API contracts from OpenAPI specification, including endpoints and security schemes.
- Implemented models for articles, orders, and webhooks to facilitate data handling.
- Developed a webhook helper for processing and enriching webhook events.
- Added tests for configuration defaults, token expiration, and webhook enrichment.

pyproject.toml

@@ -0,0 +1,38 @@
+[build-system]
+requires = ["setuptools>=69", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "booklooker-client"
+version = "0.1.0"
+description = "Python client for the Booklooker REST API with Pydantic models and webhook helpers"
+readme = "README.md"
+requires-python = ">=3.11"
+authors = [
+  { name = "GitHub Copilot" }
+]
+dependencies = [
+  "httpx>=0.27.0",
+  "pydantic>=2.8.2",
+  "PyYAML>=6.0.2"
+]
+
+[project.optional-dependencies]
+webhooks = [
+  "fastapi>=0.115.0",
+  "uvicorn>=0.30.6"
+]
+dev = [
+  "pytest>=8.3.3",
+  "pytest-asyncio>=0.24.0"
+]
+
+[tool.setuptools.package-dir]
+"" = "src"
+
+[tool.setuptools.packages.find]
+where = ["src"]
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+addopts = "-q"