feat: update footer link formatting and add shadcn-nuxt integration

- Refactored footer.vue to improve link formatting.
- Updated nuxt.config.ts to include shadcn-nuxt and added necessary HTML attributes and meta tags for SEO.
- Added new dependencies in package.json for class-variance-authority, clsx, lucide-vue-next, reka-ui, shadcn-nuxt, tailwind-merge, and tailwindcss-animate.
- Cleaned up unused template tags in headlines.vue, index.vue, and news/[provider]/[slug].vue.
- Simplified sources.vue template structure.
- Improved login.vue styles for better animation.
- Enhanced google.ts API handler for better error handling and code clarity.
- Updated find/newsOrg.ts to ensure consistent code style.
- Added CSS variables and improved Tailwind configuration in main.css and tailwind.config.js.
- Created components.json for shadcn integration and added new UI components (Alert, Button, Progress) with respective styles and variants.
- Implemented utility functions in utils.ts for class name merging and value updating.

components/ui/button/index.ts

@@ -0,0 +1,36 @@
+import { cva, type VariantProps } from "class-variance-authority";
+
+export { default as Button } from "./Button.vue";
+
+export const buttonVariants = cva(
+  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-colors focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg]:size-4 [&_svg]:shrink-0",
+  {
+    variants: {
+      variant: {
+        default:
+          "bg-primary text-primary-foreground shadow hover:bg-primary/90",
+        destructive:
+          "bg-destructive text-destructive-foreground shadow-sm hover:bg-destructive/90",
+        outline:
+          "border border-input bg-background shadow-sm hover:bg-accent hover:text-accent-foreground",
+        secondary:
+          "bg-secondary text-secondary-foreground shadow-sm hover:bg-secondary/80",
+        ghost: "hover:bg-accent hover:text-accent-foreground",
+        link: "text-primary underline-offset-4 hover:underline",
+      },
+      size: {
+        default: "h-9 px-4 py-2 rounded",
+        xs: "h-7 rounded px-2",
+        sm: "h-8 rounded-md px-3 text-xs",
+        lg: "h-10 rounded-md px-8",
+        icon: "h-9 w-9",
+      },
+    },
+    defaultVariants: {
+      variant: "default",
+      size: "default",
+    },
+  },
+);
+
+export type ButtonVariants = VariantProps<typeof buttonVariants>;