Text rendering

Text rendering is not supported and not planned. This is an absurdly complex task and the Rust ecosystem doesn't provide basically any libraries to implement this.

We need:

- [x] Font parser: [ttf-parser](https://github.com/RazrFalcon/ttf-parser).
- [x] Text shaper: [rustybuzz](https://github.com/RazrFalcon/rustybuzz) or [all-sorts](https://github.com/yeslogic/allsorts).
- [ ] Font database with a font fallback mechanism.
- [ ] High-quality glyph rasterization library. Like [ab_glyph_rasterizer](https://github.com/alexheretic/ab-glyph), but with FreeType level of quality.
- [ ] Code in `tiny-skia` that ties it all together.

The issue lists font fallback, high-quality glyph rasterization, and code in tiny-skia as unfinished areas, while font parsing and text shaping are marked complete. No file paths, tests, or specific entry points are provided; first determine the project entry points for text rendering and review the listed dependencies. Done would require the remaining checklist items to be implemented and integrated.

Written by the indexing model from the issue text.