v3.1.0

Minor Changes

• 571fda2: Rename the Mcu React surface to Mtb: the Mcu component is now Mtb, the useMcu hook is now useMtb, and the McuConfig type is now MtbConfig. The old names still work as deprecated aliases (same component, same hook, same shape) and will be removed in the next major.

• e061253: Add a toShadcn() exporter emitting concrete per-mode oklch() values.

  builder(source, options).toShadcn() returns { light, dark }, each a flat
  record of bare shadcn variable names (primary, chart-1, …) to concrete
  colors — the exact shape a shadcn registry item's cssVars field expects, so
  the result can be served as a registry:theme or registry:base item and
  installed with the standard shadcn CLI.

  Unlike toTailwind({ shadcn: true }), which emits var() aliases requiring the
  M3 variables to already be on the page, the output stands alone. Both now share
  a single mapping table, so neither can name a variable the other doesn't.

  Values come from the same merged colors toCss() emits, so every option —
  contrast included, across its full -1.0…1.0 range — lands identically in
  both exporters.

  Available from the CLI as --format shadcn. The existing --shadcn flag is
  unchanged, but now errors instead of being silently ignored when combined with
  a format other than tailwind.