Conditional blueprint modules

Blueprints have no way to express "include these modules only if X", so we have to depend on cli args and have these pseudo "meta modules"

def vis_module(viewer_backend: ViewerBackend, rerun_config: dict[str, Any] | None = None) -> Blueprint:
    match viewer_backend:
        case "rerun":
            bundle = autoconnect(
                RerunBridgeModule.blueprint(**rerun_config),
                RerunWebSocketServer.blueprint(),
                WebsocketVisModule.blueprint(),
            )
        case "none":
            bundle = autoconnect(WebsocketVisModule.blueprint())
        case _:
            raise ValueError(f"Unknown viewer_backend {viewer_backend!r}")
    return bundle

Ideally there would be a way for the blueprint itself to express this choice

Synced from DIM-1463 by jeff

Start by tracing the Blueprint and autoconnect entry points used by vis_module, then compare how the rerun and none branches currently depend on cli args and meta modules. Define what conditional inclusion should look like in a blueprint and consider how completion would be verified for both viewer_backend choices.