Phase 0: Replace Vuexy design system with custom EZSCALE foundation

- Install echarts, vue-echarts, @vueuse/core; remove @mdi/font
- Switch fonts from Inter/Public Sans to Plus Jakarta Sans/JetBrains Mono
- Delete all 38 @core SCSS files, replace with 6 new design token files
  (_variables, _mixins, _animations, _typography, _component-overrides, _layouts)
- Rewrite _marketing.scss with glass morphism and dark grid hero styles
- Update Vuetify theme from purple (#7367F0) to navy blue (#1d4ed8)
- Add pill-shaped buttons, tonal chips, rounded cards to Vuetify defaults
- Make default theme subdomain-aware (light for marketing, dark for app)
- Remove @core-scss and @configured-variables Vite aliases
- Fix AuthLayout and AppStepper to remove deleted @core SCSS imports

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

website/package.json

@@ -19,14 +19,16 @@
     "dependencies": {
         "@iconify/vue": "^5.0.0",
         "@inertiajs/vue3": "^2.3.13",
-        "@mdi/font": "^7.4.47",
         "@noble/ed25519": "^3.0.0",
         "@stripe/stripe-js": "^8.7.0",
         "@vitejs/plugin-vue": "^6.0.4",
+        "@vueuse/core": "^14.2.1",
+        "echarts": "^6.0.0",
         "pinia": "^3.0.4",
         "sass": "^1.97.3",
         "vite-plugin-vuetify": "^2.1.3",
         "vue": "^3.5.27",
+        "vue-echarts": "^8.0.1",
         "vuetify": "^3.11.8"
     }
 }