Add Container component and fix radius/maxWidth theming

- Drop buttonRadius prop; button now uses --radius via rounded-md
- Inject @theme radius mappings into ThemeProvider so rounded-* utilities
  pick up --radius inside the Tailwind CDN iframe
- Add shared Container that consumes --container-max-width set from the
  global maxWidth prop, replacing ad-hoc "container mx-auto max-w-7xl px-6"
  wrappers across commerce, landing, footer, navigation, and others
- Simplify maxWidth options to Small/Medium/Large/X-Large/Full bleed and
  shift the scale up so Large (1280px) matches the previous default

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

components/landing/image-gallery.tsx

@@ -1,5 +1,6 @@
 import { cn } from "@/lib/utils";
 import { Typography } from "@/components/Typography";
+import { Container } from "@/components/layout/Container";
 
 export type ImageGalleryProps = {
   tagline: string;
@@ -12,7 +13,7 @@ export type ImageGalleryProps = {
 export function ImageGallery({ tagline, heading, subheading, layout, items }: ImageGalleryProps) {
   return (
     <section className="bg-background py-20 md:py-28">
-      <div className="container mx-auto max-w-7xl px-6">
+      <Container>
         {(tagline || heading || subheading) && (
           <div className="mx-auto mb-12 max-w-2xl text-center">
             {tagline ? (
@@ -86,7 +87,7 @@ export function ImageGallery({ tagline, heading, subheading, layout, items }: Im
             ))}
           </div>
         )}
-      </div>
+      </Container>
     </section>
   );
 }

components/landing/newsletter-cta.tsx

@@ -1,6 +1,7 @@
 import { useState } from "react";
 import { cn } from "@/lib/utils";
 import { Typography } from "@/components/Typography";
+import { Container } from "@/components/layout/Container";
 
 export type EmailProvider = "none" | "mailchimp" | "klaviyo";
 
@@ -131,7 +132,7 @@ export function NewsletterCta({
   if (layout === "split") {
     return (
       <section className="bg-background">
-        <div className="container mx-auto max-w-7xl px-6 py-16 md:py-24">
+        <Container className="py-16 md:py-24">
           <div className="grid grid-cols-1 items-center gap-12 md:grid-cols-2">
             <div>
               {imageUrl ? (
@@ -165,7 +166,7 @@ export function NewsletterCta({
               </div>
             </div>
           </div>
-        </div>
+        </Container>
       </section>
     );
   }