[project] create pyproject.toml, readme, version file

`pdm build` even builds this package; no idea if it would be
installable/usable though

pyproject.toml

@@ -1,3 +1,16 @@
+[project]
+name = "teilchensammler"
+description = "Build a list of parts in a pile to help sorting and categorization"
+readme = "README.md"
+dynamic = [
+  "version",
+]
+requires-python = ">= 3.12"
+# dependencies are in folder .dependencies/*.in
+authors = [
+  { name = "bronsen", email = "kontakt+teilchensammler@nrrd.de" },
+]
+
 [tool.pytest.ini_options]
 pythonpath = "."
 python_files = [
@@ -10,3 +23,11 @@ addopts = [
   "--capture=sys",
 ]
 
+[build-system]
+requires = [
+  "pdm-backend",
+]
+build-backend = "pdm.backend"
+[tool.pdm.version]
+source = "file"
+path = "VERSION.py"