Typography: DM Sans & JetBrains Mono

Two typefaces, two jobs

By default, every Text in SwiftUI uses the system font — San Francisco, the typeface of iOS itself. It's excellent, and it's also what every default-looking app uses. PawWalk ships its own two:

• DM Sans — the display face: headings, buttons, body copy. Friendly, geometric.
• JetBrains Mono — a monospaced face (every character the same width), used for readouts: coordinates, distances, timers, those uppercase HUD labels. Monospace is why numbers don't jiggle as a timer ticks.

A custom font is just files shipped inside the app (this repo already wires them up in the project config). Swift loads one with Font.custom(name, size:), where name is the font's internal name like "DMSans-Bold". One catch: every weight is a separate file — there's no bold switch, only a differently-named font. Which is exactly the problem the next code solves.