docs: launch docs site and trim README

[fanyang89]

Add documentation site as a git submodule and replace the verbose README

[chatgpt-codex-connector]

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[gemini-code-assist]

Code Review

This pull request moves the project's detailed documentation, architecture diagrams, and quick-start guides from the README into a separate 'docs' submodule and a dedicated website (raftpp.cc). The README has been significantly streamlined to serve as a high-level landing page. Feedback focuses on restoring critical information to the README for better developer experience, specifically the C++23 version requirement and explanatory comments for the custom build tasks, as well as improving the formatting of the documentation link.

[gemini-code-assist]

The specific C++ version requirement (C++23) was removed from the description. It is highly recommended to keep this information in the README so users can immediately determine if their environment is compatible without having to visit the full documentation site.

Suggested change

	A modern C++ implementation of the RAFT consensus algorithm.
	A modern C++23 implementation of the RAFT consensus algorithm.

[gemini-code-assist]

Using a proper Markdown link for the documentation URL makes it more professional and ensures it is clickable in all environments. Additionally, using the domain name as the link text is often cleaner than a bare URL.

Suggested change

	**https://raftpp.cc**
	**[raftpp.cc](https://raftpp.cc)**

[gemini-code-assist]

The task commands (from go-task) are used here without explanation. Restoring the brief comments from the previous version helps users understand what each command does, especially since task is not a standard tool in the C++ ecosystem.

Suggested change

	task cmake
	task build
	task test
	task cmake # Configure CMake with dev preset
	task build # Build all targets
	task test # Run all tests