Added something like yacy to zeronet?

[yacy](https://github.com/yacy/yacy_search_server)
a p2p search engine.

No files or tests are named. Start by reviewing ZeroNet's decentralized architecture and the linked YaCy project, then clarify how a peer-to-peer search feature should fit. Done requires a concrete scope, an identified entry point, and an agreed verification plan.

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