feat: scaffold Nuxt 3 + Nuxt UI 3

Initialize Nuxt 4 project with @nuxt/ui template including Tailwind CSS v4,
TypeScript, ESLint, and Nuxt UI v3 (via @nuxt/ui package).

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

front-end/.gitignore

@@ -0,0 +1,24 @@
+# Nuxt dev/build outputs
+.output
+.data
+.nuxt
+.nitro
+.cache
+dist
+
+# Node dependencies
+node_modules
+
+# Logs
+logs
+*.log
+
+# Misc
+.DS_Store
+.fleet
+.idea
+
+# Local env files
+.env
+.env.*
+!.env.example