Rebrand store as Pulse with athletic theme and shared typography

- Pulse theme tokens in app.schema.json: Archivo Black headings (weight 400)
  + Inter body, white bg / black pill buttons, xl radius, AI-generated
  athletic imagery
- Add headerFontWeight theme prop so single-weight fonts (Archivo Black)
  load and render correctly; ThemeProvider applies font-family + weight
  inline so Typography works regardless of `as` element
- New shared Heading component (tagline / title / subtitle with size +
  align + tone variants) and Typography caption variant for taglines;
  refactor features, faq, cta, testimonials, products-carousel,
  products-grid, collection-grid, recommended-products, image-gallery,
  newsletter-cta to use them
- Hero accepts a `buttons` array (label / href / variant) replacing
  primaryCta/secondaryCta; cover-image component removed and existing
  cover blocks migrated to Hero blocks with `buttons: []`
- Newsletter CTA uses shadcn Button + Input so it inherits theme radius;
  stacked layout fixed to keep the image
- Product/collection card titles use Typography subtitle variants
  (font-body), heading font weight is theme-controlled
- Remove orphan commerce/shop-header.tsx and commerce/shop-footer.tsx;
  the editor-driven navigation/footer are the live chrome

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

components/testimonials/testimonials.tsx

@@ -1,6 +1,6 @@
 import { useState } from "react";
 import { ArrowLeft, ArrowRight } from "lucide-react";
-import { Typography } from "@/components/Typography";
+import { Heading } from "@/components/Heading";
 
 export type TestimonialsProps = {
   tagline: string;
@@ -21,12 +21,12 @@ export function Testimonials({ tagline, heading, items }: TestimonialsProps) {
   return (
     <section className="bg-muted/40 py-20 md:py-28">
       <div className="container mx-auto max-w-4xl px-6 text-center">
-        {tagline ? (
-          <p className="mb-3 text-xs uppercase tracking-[0.2em] text-muted-foreground">
-            {tagline}
-          </p>
-        ) : null}
-        {heading ? <Typography variant="h2">{heading}</Typography> : null}
+        <Heading
+          tagline={tagline}
+          title={heading}
+          align="center"
+          size="lg"
+        />
 
         {item ? (
           <div className="relative mt-12">