Add individual tire pages with SEO (2.0 Pillar 2, Phase 2A)

Give every tire a server-rendered, indexable URL at /tires/{slug}/ so
tires can rank on their own instead of being trapped inside the catalog
shortcode. Content (specs, price, Roamer efficiency, owner reviews) is
in the initial HTML — no JS required for crawlers.

- Schema: add a `slug` column (migration 17), auto-generated from
  brand+model+size on insert/update with collision suffixing, and
  backfilled for existing rows. New get_tire_by_slug / sync_tire_slug /
  backfill_slugs helpers. slug appended to the frontend row arrays.
- Routing: new RTG_Tire_Page mirrors the RTG_Tire_Review standalone
  pattern (rewrite rule, template_redirect render, security headers).
  Unknown slug -> real 404; legacy /tires/{tire_id}/ -> 301 canonical.
- Structured data: factor the per-tire Product builder out of
  RTG_Schema into reusable build_product_item / build_single_product,
  so the page emits a dedicated Product node (not just the catalog
  ItemList) plus BreadcrumbList. build_description in RTG_Meta made
  public/static for reuse.
- Template: frontend/templates/tire-page.php renders title/meta/
  canonical/OG, breadcrumb, hero, full spec sheet (efficiency omitted
  per its discontinuation), Roamer block, and server-rendered reviews.
- Cards: tire titles now link to /tires/{slug}/ (tirePageUrl localized,
  subdirectory-safe); .tire-card-model-link styling added.

Build regenerated; 83/83 JS tests pass. Remaining SEO work (sitemap,
?tire= canonical consolidation, admin slug setting, on-page click
tracking) tracked in ROADMAP-2.0.md.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: RivianTrackr

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to the Rivian Tire Guide plugin will be documented in this f
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
+## [Unreleased]
+
+### Added
+- **Individual, crawlable tire pages (2.0 Pillar 2, Phase 2A).** Every tire now has a server-rendered, indexable URL at `/tires/{slug}/` — tire content (specs, price, Roamer efficiency, owner reviews) is in the initial HTML, not injected by JS. Adds a `slug` column (migration 17, auto-generated from brand+model+size and backfilled), a new `RTG_Tire_Page` route mirroring the standalone review-page pattern, per-tire `<title>`/meta/canonical/OG tags, and dedicated `Product` + `BreadcrumbList` JSON-LD (the `RTG_Schema` product builder was factored out for reuse instead of only emitting a catalog-wide `ItemList`). Tire-card titles now link to these pages; legacy `/tires/{tire_id}/` URLs 301 to the canonical slug. Remaining SEO work (sitemap entries, `?tire=` canonical consolidation, admin slug setting, on-page click tracking) is tracked in ROADMAP-2.0.md.
+
 ## [1.51.0] - 2026-07-02
 
 ### Changed

frontend/css/rivian-tires.css

@@ -886,6 +886,13 @@
   color: var(--rtg-text-heading);
   line-height: 1.2;
 }
+.tire-card-model-link {
+  color: inherit;
+  text-decoration: none;
+}
+.tire-card-model-link:hover {
+  color: var(--rtg-accent);
+}
 
 /* Tags row */
 .tire-card-tags {

frontend/css/rivian-tires.min.css

@@ -206,7 +206,7 @@ export function createSingleCard(row) {
     tireId, size, diameter, brand, model, category, price, warranty, weight, tpms,
     tread, loadIndex, maxLoad, loadRange, speed, psi, utqg, tags, link, image,
     /* efficiencyScore */ , /* efficiencyGrade */ , reviewLink, /* createdAt */ ,
-    roamerEfficiency, roamerTotalKm, roamerVehicleCount, roamerVehicleBreakdown
+    roamerEfficiency, roamerTotalKm, roamerVehicleCount, roamerVehicleBreakdown, slug
   ] = row;
 
   if (!VALIDATION_PATTERNS.tireId.test(tireId)) {
@@ -345,7 +345,18 @@ export function createSingleCard(row) {
 
   const modelEl = document.createElement('div');
   modelEl.className = 'tire-card-model';
-  modelEl.textContent = safeString(model);
+  // Link the title to the individual tire page (crawlable, canonical URL).
+  const tirePageBase = (typeof rtgData !== 'undefined' && rtgData.settings && rtgData.settings.tirePageUrl) ? rtgData.settings.tirePageUrl : '';
+  const safeSlug = safeString(slug).trim();
+  if (tirePageBase && safeSlug) {
+    const modelLink = document.createElement('a');
+    modelLink.className = 'tire-card-model-link';
+    modelLink.href = tirePageBase + encodeURIComponent(safeSlug) + '/';
+    modelLink.textContent = safeString(model);
+    modelEl.appendChild(modelLink);
+  } else {
+    modelEl.textContent = safeString(model);
+  }
   bodyEl.appendChild(modelEl);
 
   const ratingDiv = document.createElement('div');