fix: remove ty configuration section to use defaults

Remove the [tool.ty] section entirely as ty is in early alpha and
the configuration format is not well documented. Let ty use its
default configuration which should work for standard project layouts.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: dguido

{{cookiecutter.project_slug}}/pyproject.toml

@@ -59,9 +59,7 @@ Source = "https://github.com/{{ cookiecutter.github_username }}/{{ cookiecutter.
 # don't attempt code coverage for the CLI entrypoints
 omit = ["{{ cookiecutter.__project_src_path }}/_cli.py"]
 
-[tool.ty]
-# Astral's experimental type checker
-src = ["src"]
+# ty configuration - using defaults for now as ty is in early alpha
 
 [tool.ruff]
 line-length = 100