P5.2 — Generative typography/motion/radius scale primitives

[dbanksdesign]

Implements P5.2 from IMPROVEMENTS.md per specs/type-motion-radius-scale-generation.md (core-only scope — the design-system wiring lives in var-ui).

What's new

New typestyles/token-scale subpath (packages/typestyles/src/token-scale.ts) with three generic numeric ramp generators, so a theme author writes 2-3 numbers instead of hand-picking a whole ladder:

• generateGeometricScale({ base, ratio, steps, round? }) — base * ratio ** offset for each signed integer offset in steps (font-size-style modular ladders). Offset 0 always returns exactly base.
• generateLinearScale({ base, multiplier, steps, round? }) — base * step * multiplier for each ordinal in steps (radius-style grid ladders). multiplier: 0 is allowed (all zeros).
• expandDurationBand({ base, ratio, roundTo? }) — expands one duration anchor into { min, base, max } (min = base * ratio, max = base / ratio), rounded to the nearest 5ms by default so bands look hand-picked instead of computed (no 93.75ms).

Pure numeric outputs, zero naming opinions — no fontSize/radius/fast vocabulary in core. Rounding defaults to whole numbers (Math.round), with round/roundTo overrides. Clear [typestyles]-prefixed errors guard non-finite inputs, ratio <= 0, roundTo <= 0, and non-integer geometric offsets.

Wiring mirrors typestyles/color-scale (P5.1): tsup entry src/token-scale-entry.ts, ESM+CJS exports block, separate subpath with zero impact on the main bundle (bundle-size check still passes: 16794 / 16900 budget). Docs added to api-reference.md and theming-patterns.md alongside the color-scale sections; changeset .changeset/p5-2-token-scale.md (typestyles: minor); P5.2 checked off in IMPROVEMENTS.md.

Test evidence

• pnpm test (packages/typestyles): 26 files / 381 tests passed (includes new token-scale.test.ts: 23 tests covering deterministic math, rounding defaults + overrides, step ordering, steps=1/empty edge cases, and zero/negative/non-finite guards)
• pnpm typecheck: pass
• pnpm build: pass — dist/token-scale.{js,cjs,d.ts,d.cts} emitted; verified import/require of typestyles/token-scale both resolve and return correct values at runtime
• pnpm lint: pass (1 pre-existing warning in color-scale.test.ts, none in new code)

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