add docs

Author: tlambert03

src/scyjava/_stubs/_hatchling.py

@@ -1,7 +1,23 @@
-"""Hatchling build hook for generating Java stubs."""
+"""Hatchling build hook for generating Java stubs.
+
+To use this hook, add the following to your `pyproject.toml`:
+
+```toml
+[build-system]
+requires = ["hatchling", "scyjava"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.hooks.scyjava]
+maven_coordinates = ["org.scijava:parsington:3.1.0"]
+prefixes = ["org.scijava"]  # optional ... can be auto-determined from the jar files
+```
+
+This will generate stubs for the given maven coordinates and prefixes. The generated
+stubs will be placed in `src/scyjava/types` and will be included in the wheel package.
+This hook is only run when building a wheel package.
+"""
 
 import logging
-import shutil
 from pathlib import Path
 
 from hatchling.builders.hooks.plugin.interface import BuildHookInterface