A view component: a pure function from a props bag to something the engine
can render to a string — a JSX node (@hono/hono/jsx), an
HtmlEscapedString (the html tagged template), or a plain string
(a by-name template adapted per §3.6 of the M92 plan).
The return type is deliberately unknown: one type must cover every
renderable shape without this package importing a JSX runtime.
(props: P) => unknown