Swap to shadcn components and polish the design

Components (added via the shadcn MCP/CLI):
- Navbar: NavigationMenu on desktop, Sheet on mobile; drops
  Navbar.module.css and the hand-rolled slide-down menu
- Buttons: shadcn Button via a shared ContactButtons component
  (replaces Button.js and its CSS module)
- Card for price cards, testimonials, the business block and plan;
  Table for prices; Input/Textarea/Label/NativeSelect/RadioGroup and
  Alert in the quote form; Separator in the footer
- Components import cn from @/lib/utils (not the new "cn" package);
  accordion moved to the unified radix-ui package

Design tweaks:
- Geist Sans is actually applied (font variables were on <body>, but
  Tailwind reads them on <html>, so the site fell back to system fonts)
- Theme primary set to the existing brand blue; slightly smaller radius
- Balanced, tighter heading tracking; muted secondary text
- 44px contact buttons; 16px FAQ text; tighter homepage spacing
- Full-width selects with 16px text on phones (no iOS zoom)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/app/components/PriceTable.js

@@ -0,0 +1,18 @@
+import { Table, TableBody, TableCell, TableRow } from "@/components/ui/table";
+
+export default function PriceTable({ items, className }) {
+  return (
+    <Table className={className}>
+      <TableBody>
+        {items.map(({ item, price }) => (
+          <TableRow key={item}>
+            <TableCell className="py-3 pl-0 whitespace-normal">{item}</TableCell>
+            <TableCell className="py-3 pr-0 text-right font-semibold whitespace-normal text-primary">
+              {price}
+            </TableCell>
+          </TableRow>
+        ))}
+      </TableBody>
+    </Table>
+  );
+}