Revise README.md for clarity and formatting

[GaspardKirira]

Updated README.md to improve formatting, add new features, and clarify project goals.

Pull Request Checklist

Thank you for contributing to Vix.cpp.
Please review this checklist before submitting your Pull Request.

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Summary

What does this PR do?

Related issues

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Type of Change

Please check the relevant option(s):

• New feature
• Bug fix
• Refactoring (no behavior change)
• Performance improvement
• Documentation update
• Build / tooling / CI change
• Other (please describe):

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Code Quality

• Code follows the project style and conventions
• C++20 (or newer) features are used appropriately
• No unnecessary complexity introduced
• No unused code, headers, or debug logs
• Public APIs are documented where applicable

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Tests

• Existing tests pass locally
• New tests were added for new behavior or fixes
• Tests are located under tests/ or unittests/
• ctest --output-on-failure passes

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Performance (if applicable)

• Change has no negative performance impact
• Benchmarks were run for performance-sensitive changes
• Results are included or described in the PR

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CLI / UX (if applicable)

• CLI output is clear and consistent
• Help (-h / --help) output was updated if needed
• Exit codes follow project conventions

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Documentation

• Documentation was updated (README / docs)
• Examples were added or updated if relevant
• Comments explain non-obvious logic

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CMake / Build System

• CMakeLists changes are minimal and scoped
• Uses target_* commands only (no global includes)
• Targets are exported under the Vix:: namespace

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Final Checks

• I have rebased on the latest dev branch
• Commit messages follow Conventional Commits
• This PR is ready for review

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Additional Notes

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By submitting this Pull Request, I confirm that my contribution is licensed
under the same MIT License as the Vix.cpp project.