Property key autocomplete in view! macro is not working

Users are unable to discover the required (and optional) props of a component they want to use. They cannot simply begin to write `<SomeComp |>` and hit the IDE autocomplete shortcut at cursor position '|' in a view! macro. No meaningful thing will be shown. Neither actually defined props, nor inherently available things like `on` handler attachment, `class`, `style`, etc. This inability to discover goes against common user expectations. It may slow down development, as it may require more jumps to external (to the view! macro call) component definitions and/or external resources (documentation, websites, ....) or roundtrips with the compiler. Due to https://github.com/leptos-rs/leptos/issues/4628, roundtrips with the compiler are also inefficient.