Render `src/app/views/errors.zig` view (`index` action) when an
unexpected error occurs. If the view does not exist, try rendering
`public/404.html`, `public/500.html` (etc.), finally falling back to a
standard basic HTML/JSON response.
Remove old bash script for setting up a new project, do everything in
Zig to make it platform agnostic and give us an easy place to add
scaffolding commands in future.
Generate views defined with `request: *jetzig.http.StaticRequest` as
static content into `static/` directory so that exported JSON and HTML
can be rendered direct from disk, skipping runtime rendering.