Update comments

{{ cookiecutter.namespace }}/pyproject.toml

@@ -50,18 +50,26 @@ dependencies = [
 # "Discussions" = "https://github.com/organization/package/discussions"
 # "Changelog" = "https://github.com/organization/package/blob/main/CHANGELOG.md"
 
-# Include only the source code under src/pynwb/{{ cookiecutter.py_pkg_name }} and the spec files under spec.
-# Install the spec files in the wheel under the {{ cookiecutter.py_pkg_name }} package.
-# {{ cookiecutter.py_pkg_name }}/__init__.py will look there first for the spec files.
+# Include only the source code under `src/pynwb/{{ cookiecutter.py_pkg_name }}` and the spec files under `spec`
+# in the wheel.
 [tool.hatch.build.targets.wheel]
 packages = [
     "src/pynwb/{{ cookiecutter.py_pkg_name }}",
     "spec"
 ]
 
+# Rewrite the path to the `spec` directory to `{{ cookiecutter.py_pkg_name }}/spec`.
+# `{{ cookiecutter.py_pkg_name }}/__init__.py` will look there first for the spec files.
+# The resulting directory structure within the wheel will be:
+# {{ cookiecutter.py_pkg_name }}/
+# ├── __init__.py
+# ├── spec
+# └── widgets
 [tool.hatch.build.targets.wheel.sources]
 "spec" = "{{ cookiecutter.py_pkg_name }}/spec"
 
+# The source distribution includes everything in the package except for the `src/matnwb` directory and
+# git and github-related files.
 [tool.hatch.build.targets.sdist]
 exclude = [
     ".git*",