Implement authentication phase with Cidaas OAuth2 integration

- Add authentication middleware to protect routes
- Create API endpoints for login, logout, registration, and user info
- Develop UI components for login and registration forms
- Integrate VeeValidate for form validation
- Update environment configuration for Cidaas settings
- Add i18n support for English and German languages
- Enhance Tailwind CSS for improved styling of auth components
- Document authentication flow and testing procedures

app/components/ui/input/index.ts

@@ -0,0 +1,27 @@
+import type { VariantProps } from 'class-variance-authority'
+import { cva } from 'class-variance-authority'
+
+export { default as Input } from './Input.vue'
+
+export const inputVariants = cva(
+  'flex w-full rounded-xl border border-white/20 bg-white/10 px-4 py-3 text-base text-white ring-offset-transparent file:border-0 file:bg-transparent file:text-sm file:font-medium file:text-foreground placeholder:text-white/50 transition-all duration-300 hover:bg-white/15 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/50 focus-visible:ring-offset-0 disabled:cursor-not-allowed disabled:opacity-50',
+  {
+    variants: {
+      variant: {
+        default: '',
+        error: 'border-destructive focus-visible:ring-destructive',
+      },
+      size: {
+        default: 'h-12',
+        sm: 'h-10 text-sm px-3 py-2',
+        lg: 'h-14 text-lg px-5 py-4',
+      },
+    },
+    defaultVariants: {
+      variant: 'default',
+      size: 'default',
+    },
+  }
+)
+
+export type InputVariants = VariantProps<typeof inputVariants>