This commit introduces several significant enhancements to the Linux installation guide for Flutter. Key changes include:

1. Expanded 'System Requirements' section with clearer, more concise language.
2. Added a new 'Understanding Linux Commands' section to familiarize users with common Linux commands used throughout the installation process.
3. Included a new section on 'Installing Snap on Ubuntu,' guiding users through the process of installing and using Snap on their Ubuntu systems.
4. Revamped the 'Flutter Installation', 'Android Studio Setup', and 'Chrome Setup' sections to provide more detailed, step-by-step instructions.
5. Incorporated a comprehensive 'Glossary' at the end of the document, providing definitions for key terms and commands.

The goal of these changes is to make the installation guide more accessible, user-friendly, and informative for users of all experience levels.

Co-authored-by: Parker Lougheed <parlough@gmail.com>