update taskfile to generate types during `build` (#55628)
When running the `dev` task, types aren't emitted so there's a good chance of running into a TypeError like:
```
Type error: Module '"next/dist/lib/metadata/types/metadata-interface.js"' has no exported member 'ResolvingMetadata'.
```
during a `next build` from within the monorepo.
This creates a task to run `types` from within taskr as part of the build step.
