Add RAR Storefront WordPress theme

Implements the Reply All Regrets™ frontend design: retro office aesthetic
with manila/ink/stamp-red/olive palette, Fraunces + JetBrains Mono + Inter
typography. Includes homepage, category, product detail, blog, about, cart
templates with WooCommerce integration and interactive JS (filter, sort, gallery).

Co-Authored-By: Paperclip <noreply@paperclip.ing>

theme/404.php

@@ -0,0 +1,18 @@
+<?php get_header(); ?>
+
+<section style="padding:120px 56px;text-align:center;">
+    <div class="rar-form-tag" style="margin-bottom:24px;justify-content:center;">ERROR 404 · PAGE NOT FOUND · MISFILED</div>
+    <h1 style="font-family:var(--serif);font-size:88px;font-weight:500;line-height:0.95;margin:0 0 24px;letter-spacing:-0.03em;">
+        This page<br>has been<br><em style="color:var(--stamp);font-style:italic;">parked in the lot.</em>
+    </h1>
+    <p style="font-size:16px;line-height:1.6;color:var(--ink-muted);max-width:440px;margin:0 auto 40px;">
+        The page you're looking for has been circled back on indefinitely.
+        Try navigating from the top, or use the search.
+    </p>
+    <div style="display:flex;gap:12px;justify-content:center;">
+        <a href="<?php echo esc_url(home_url('/')); ?>" class="rar-btn rar-btn--stamp">← Back to shop</a>
+        <a href="<?php echo esc_url(get_permalink(wc_get_page_id('shop'))); ?>" class="rar-btn rar-btn--ghost">Browse products</a>
+    </div>
+</section>
+
+<?php get_footer(); ?>