Add Bookstore Inventory Mini-Project Demonstrating Core Rust Concepts

[davidfertube]

Overview

This PR introduces a new mini-project, Bookstore Inventory CLI, under 15_mini_project/.
The project consolidates and demonstrates all the core Rust programming concepts covered in this course within a practical, interactive command-line application.

Features

• Bookstore Inventory Manager: A CLI app that allows users to add and list books by genre.
• Demonstrates Key Rust Topics:
  • Variables and constants
  • Structs and enums (e.g., Book, Genre)
  • Ownership and borrowing practices
  • Custom functions and error handling using Result
  • Conditionals and loops
  • Compound types and collections (Vec, HashMap)
  • User input/output with std::io
  • Shadowing, pattern matching, and more

How it works

• Users can:
  • Add a new book by entering title, author, genre, and page count.
  • List all books or filter books by a specific genre.
  • Exit the CLI at any time.
• The implementation validates user input and properly handles errors.

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This addition serves as a capstone to reinforce understanding of Rust fundamentals via practical application.