Add web-based demo of unfinished Bitcoin v0.01 alpha features

[nozmo-king]

This demo recreates the marketplace and poker features that were designed but never fully implemented in the original Bitcoin v0.01 alpha client.

Features demonstrated:

• Bitcoin Marketplace with atom-based reputation system (from market.cpp/h)
• Poker room with Texas Hold'em interface (from uibase.cpp/h)
• Era-appropriate Windows XP styling matching 2009 aesthetic
• Interactive single-page web application

The demo is based on actual source code analysis:

• CUser, CProduct, CReview classes for marketplace
• CPokerLobbyDialogBase and CPokerDialogBase for poker UI
• Atom propagation system for decentralized reputation

Files added:

• demo/index.html - Interactive web demo
• demo/README.md - Historical context and documentation

[brain-zhang]

Hi,

Thank you for your pull request! This is a fascinating contribution and an excellent piece of historical documentation for the bitcoin_satoshi project.

It's truly insightful to see a recreation of the Marketplace and Poker room features that were designed but ultimately not implemented in the original v0.01 alpha client. This provides valuable context regarding the initial scope and vision for Bitcoin.

Since the proposed changes appear to be adding documentation and a historical demo rather than code intended for compilation into the original client, I believe the best place for this material is within the project's Wiki or a dedicated section of the documentation. This will make it easily discoverable and ensure it doesn't clutter the main source repository.

Next Steps:

• I will be taking the content from your demo/index.html and demo/README.md and integrating it into our project's Wiki to serve as a high-value historical reference, possibly titled "Historical Features: Marketplace and Poker."I

• will close this PR as the content will be merged into the Wiki rather than the codebase.

Thank you again for the detailed analysis and for sharing this excellent historical insight into the $v0.01$ code. Contributions that add to the historical understanding of the project are greatly appreciated!