feat: scaffold project structure with package dirs and mistralai dependency

- Create bulkgen/ package with __init__.py
- Create bulkgen/providers/ subpackage with __init__.py
- Add mistralai>=1.0.0 to dependencies
- Add [project.scripts] entry point and [build-system] with hatchling
- Add .bulkgen.state.yaml to .gitignore

pyproject.toml

@@ -6,16 +6,21 @@ readme = "README.md"
 requires-python = ">=3.13"
 dependencies = [
     "blackforest>=0.1.3",
+    "mistralai>=1.0.0",
     "networkx>=3.6.1",
     "pydantic>=2.12.5",
     "pydantic-settings[yaml]>=2.12.0",
-    "pyright>=1.1.408",
     "typer>=0.23.1",
 ]
 
+[project.scripts]
+bulkgen = "main:main"
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
 [dependency-groups]
 dev = [
-    "pyright>=1.1.408",
     "pytest>=9.0.2",
-    "ruff>=0.15.1",
 ]