Add workflow tooling: claude2figma skills, Storybook addons, Figma permissions

Install @storybook/addon-designs for embedding Figma frames in stories
and claude2figma skills (preflight, component-rules, style-binding,
reference-interpreter) for enforcing design token compliance when
writing to Figma. Add PostToolUse hook for use_figma QA reminders and
pre-allow Figma MCP + Code Connect tools in settings.json.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.storybook/main.ts

@@ -9,6 +9,7 @@ const config: StorybookConfig = {
     "@storybook/addon-vitest",
     "@storybook/addon-a11y",
     "@storybook/addon-docs",
+    "@storybook/addon-designs",
     "@storybook/addon-mcp"
   ],
   "framework": "@storybook/react-vite"