renderContentPreview crashed on the Windows prebuilt with "Failed to
convert napi value Null into rust type `u8`" (and the related `bool`
variant) because the wrapper forwarded `null` to napi-rs 3's
`Option<Ellipsis>` / `Option<bool>` parameters; the Windows binding
rejects null where Linux/macOS tolerates it. `maxWidth` was also passed
through unchecked, so a stray null/undefined upstream blew up the
required `u32` everywhere. Pass concrete defaults that mirror the Rust
`unwrap_or`s and clamp `maxWidth` to a sane non-negative integer.
Fixes#848
can1357
d731e57513