Migrate Tailwind styles to design-system package (#5794)

## Summary

Consolidates Tailwind configuration and styles into a shared
`@comfyorg/design-system` package for reuse across monorepo apps.

The goal was not to make changes to how the design system works; merely
to separate it cleanly. I _would_ strongly recommend some drastic
sweeping changes, however I believe that should be done after the
migration.

## Changes

- **What**: Migrates CSS files, Tailwind config, and custom icons to
design-system package
- **Dependencies**: Moves `@iconify-json/lucide` and `@iconify/tailwind`
to design-system package

package.json

@@ -42,8 +42,6 @@
   },
   "devDependencies": {
     "@eslint/js": "^9.35.0",
-    "@iconify-json/lucide": "^1.2.66",
-    "@iconify/tailwind": "^1.2.0",
     "@intlify/eslint-plugin-vue-i18n": "^4.1.0",
     "@lobehub/i18n-cli": "^1.25.1",
     "@nx/eslint": "21.4.1",
@@ -107,6 +105,7 @@
     "@alloc/quick-lru": "^5.2.0",
     "@atlaskit/pragmatic-drag-and-drop": "^1.3.1",
     "@comfyorg/comfyui-electron-types": "0.4.73-0",
+    "@comfyorg/design-system": "workspace:*",
     "@comfyorg/tailwind-utils": "workspace:*",
     "@iconify/json": "^2.2.380",
     "@primeuix/forms": "0.0.2",