docs: restore or remove referenced realtime LiveKit examples

[lanycrost]

Summary

examples/README.md references realtime LiveKit examples, but this checkout does not contain the referenced examples/realtime/livekit-* directories.

Evidence

The README lists:

• examples/realtime/livekit-chat/
• examples/realtime/livekit-translation/
• examples/realtime/livekit-voice/

Local inspection during the SDK typed transport config migration found no examples/realtime tree in this checkout.

Why this matters

The current LiveKit chat/translation verification depends on concrete Story YAML shapes. Without the examples, it is harder to prove whether a pipeline should route directly from packet.text, whether a memory step is intentionally required, and whether docs/examples match the latest SDK/Bobravoz streaming ABI.

Acceptance criteria

• Restore the realtime LiveKit example directories, or update examples/README.md to remove/defer those links.
• Include at least one example that demonstrates LiveKit chat packet.text feeding a downstream OpenAI chat/translation runtime input without a memory workaround.
• Include a separate example or note when conversation-memory is required for actual history, not for packet routing.

Related

• https://github.com/orgs/bubustack/discussions/77
• Resolve the remaining packet ABI inconsistencies under one canonical contract bubu-sdk-go#74