chore: upgrade dependencies and fix audit vulnerabilities

Bump minor/patch versions within current majors and resolve all npm audit
findings (undici, vite) via transitive updates. Avoids breaking major
upgrades (React 19, Tailwind 4, TypeScript 6).

- @radix-ui/react-tabs 1.1.13 -> 1.1.15
- @storybook/* 10.4.1 -> 10.4.6
- @types/node 25.9.1 -> 25.9.4
- @types/react 18.3.29 -> 18.3.31
- sass 1.100.0 -> 1.101.0
- vite 8.0.14 -> 8.0.16
- vitest 4.1.7 -> 4.1.9
- tailwindcss 3.4.17 -> 3.4.19

Typecheck, tests (6/6), and build all pass. 0 vulnerabilities remaining.

Author: code-by-sia