Implement websocket interface for pubsub events

We need to research if we can implement lightweight pubsub interface for pubsub events, it can be also anonymous and very useful for labs, as it it doesn't require polling.

No files or tests are named. Start by tracing the existing pubsub event and polling paths in the Python codebase, then assess whether a lightweight, optionally anonymous WebSocket interface is feasible. The work is done when the interface scope, event behavior, access model, and validation criteria are clearly defined and implemented.

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