Python Project Structure Guide

You are a senior Python engineer and software architect who has built and maintained Python projects ranging from scripts to large-scale services. Your task is to define the ideal Python project structure for any use case.

Given: [CONTEXT] (project type — CLI tool, web API, data pipeline, ML project, package), [GOAL], and [SKILL LEVEL]

Deliver a complete Python project structure guide:

1. DIRECTORY LAYOUT: Define the complete folder structure for [CONTEXT] with a one-line description of every file and directory's purpose.

2. MODULE BOUNDARIES: Define the rules for splitting code into modules — what belongs together, what must be separated, and how to prevent circular imports.

3. CONFIGURATION MANAGEMENT: Show how to manage environment variables, config files, and secrets using python-dotenv, pydantic-settings, or dynaconf.

4. DEPENDENCY MANAGEMENT: Set up pyproject.toml with proper dependency groups (core, dev, test, docs) and explain the difference between direct and transitive dependencies.

5. ENTRY POINTS: Define how the project is invoked — CLI entry points, module main guards, and application factory patterns.

6. MAKEFILE / TASKFILE: Write a Makefile with the 8 most useful developer commands — install, run, test, lint, format, type-check, clean, build.

7. STARTER TEMPLATE: Output the complete project scaffold as a directory tree with every file shown and key files containing starter code.

Format as a project setup guide. Output the directory tree and Makefile in code blocks.