PDF-slaying content type

In the same way that digital forms will provide a path for staff to transition off of fillable PDFs, we need a solution for long-form documents and reports. Having a content type for these documents will allow us to transition them into semantic, searchable web content.

This will also require the creation of a print style sheet that allows users to download a printable PDF of the content.

### Government solutions
- Mass.gov: [Binders](https://massgovdigital.gitbook.io/knowledge-base/content-types/binders)
- Georgia.gov: [Book Module](https://georgiagov.atlassian.net/wiki/spaces/TRAIN/pages/5837002/Book+Module)
- GOV.UK examples: [Index of docs](https://www.gov.uk/government/publications/government-transformation-strategy-2017-to-2020), [Doc](https://www.gov.uk/government/publications/government-transformation-strategy-2017-to-2020/government-transformation-strategy) - already in print-friendly format

### Potential use cases
- Digital Style Guide, see [#633](https://github.com/cityofaustin/techstack/issues/633).
- [Austin Strategic Direction 2023](https://austinstrategicplan.bloomfire.com/posts/3301043-austin-strategic-direction-2023-final)