docs(api): Document WebSocket event subscription types and payload formats

[kike-alt]

Context

Real-time WebSocket Gateway events require documented channel names and payload interfaces.

Acceptance criteria

• Document WebSocket channels (e.g., sessionUpdated, guessResult) in docs/WEBSOCKET_API.md.
• Include TypeScript interface definitions for emitted event payloads.
• Document socket authentication handshake procedure.

Implementation notes

Create docs/WEBSOCKET_API.md documentation file.

[dahmeezy]

@dahmeezy has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I would love to work on this issue please assign it to me

ℹ️ Repo Maintainers: To accept this application, review their application or assign @dahmeezy to this issue.

[demilade18-git]

@demilade18-git has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello, I'm interested in taking this issue on.

I've worked on blockchain and Web3 projects, including Stellar and Soroban smart contracts, alongside traditional full-stack web development. I'm comfortable moving between frontend, backend, and on-chain work.

I understand what's being asked here and I'm confident I can implement this correctly and efficiently.

I'd appreciate being assigned to this issue and look forward to contributing.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @demilade18-git to this issue.

[drips-wave]

Congratulations, @demilade18-git! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @demilade18-git: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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