Add Linux environment setup and build instructions to README

[gesslar]

TL;DR

Added detailed environment setup instructions for Linux, specifically Fedora 43.

What changed?

• Added a new "Preparing the Environment" section with instructions for Linux/Fedora 43
• Added steps to install SDKMAN! and Gradle
• Enhanced the build instructions with additional steps:
  • Creating the Gradle wrapper
  • Making gradlew executable
  • Running go mod tidy for dependency management
• Separated build instructions into Linux and Windows sections for clarity

How to test?

1. Follow the new environment setup instructions on a Fedora 43 system
2. Execute the build steps in sequence to verify they work correctly
3. Confirm the formatter builds successfully

Why make this change?

To improve the onboarding experience for new contributors, especially those using Linux/Fedora, by providing clear and comprehensive setup instructions. The additional build steps help prevent common issues that might occur during the initial setup process.