Add v2 Text typography primitive

Implement the first v2 typography component from the Probo Radix UI
Figma: a Text primitive rendering a single span with size, weight,
align, color, and highContrast variants (color x highContrast
resolves to the sand/gold/red/green/amber/sky text step 11 or 12),
plus a paired TextSkeleton. Styling is tailwind-variants only, with
the scale shared through a variants module per the kit guides.

Stand up a theme-isolated v2 Storybook (.storybook-v2) loading the
v2 theme with a light/dark toggle, since v1 and v2 cannot share one
Tailwind build; the v1 build now excludes src/v2.

Signed-off-by: Émile Ré <emile@probo.com>

packages/ui/.storybook-v2/preview.css

@@ -0,0 +1,18 @@
+/* Copyright (c) 2026 Probo Inc <hello@probo.com>.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+@import "tailwindcss";
+@import "../src/v2/theme.css";
+@source "../src/v2";