Add uvx usage instructions and package configuration

The README now includes a new "Usage with uvx" section showing how to
run the tool directly without installation. The pyproject.toml has been
updated to add the package script entry point and configure setuptools
to include the src directory.

pyproject.toml

@@ -18,8 +18,14 @@ dependencies = [
     "transformers>=4.50.2",
     "yt-dlp>=2025.3.27",
 ]
+[project.scripts]
+audio-summary = "summary:main"
+
 [tool.setuptools]
-py-modules = []
+py-modules = ["summary"]
+
+[tool.setuptools.package-dir]
+"" = "src"
 
 [tool.ruff]
 # Exclude a variety of commonly ignored directories.