doc: From General MCP Server to AI-Powered Minecraft Assistant

[cfc4n]

This pull request updates the documentation for the MoLing project, transitioning its focus from a general-purpose MCP server to an AI-powered Minecraft server assistant. The changes include rebranding, updating descriptions, and restructuring usage instructions across multiple language-specific README files.

Documentation Updates:

Rebranding and Focus Shift:

• Updated the project description to position MoLing as an AI assistant for Minecraft, emphasizing intelligent building, redstone circuit design, and natural language interaction to enhance the gaming experience. (README.md, README_ZH_HANS.md) [1] [2]

Language-Specific Changes:

• Removed the Japanese README file (README_JA_JP.md) and corresponding language links in other README files, consolidating the focus on English and Simplified Chinese.

Usage Instructions:

• Added detailed step-by-step instructions for configuring the Minecraft server, client, and AI agent, including examples for modifying configuration files and setting up tools like Cherry Studio. (README.md, README_ZH_HANS.md) [1] [2]

Visual Enhancements:

• Replaced outdated screenshots and demo links with new placeholders (@TODO) and updated images showcasing the Minecraft-specific features. (README.md, README_ZH_HANS.md) [1] [2]

These updates modernize the documentation, align it with the new project direction, and provide clearer guidance for users.