Publish a reactive value to a shinyreact client (the ui.tsx pattern)
Source: R/render.R
reactive_output.RdServer-side counterpart to useShinyOutputValue(). Assign to output[[id]];
a React client reads the value by id. There is no UI placeholder — the
client owns all UI. Accepts any JSON-serializable value (passed through
unchanged).
Usage
reactive_output(expr, env = parent.frame(), quoted = FALSE)