Rebuild on the RealBrain design system and retarget SEO to content credentials

Search Console (Jun 4 – Sep 3) shows the page ranking on the first results
page for "content credentials" queries while converting badly: "ai
credentials remover" at 113 impressions and 0.88% CTR from position 6.7,
"remove content credentials from image online" at 2.15% from position 5.0,
"remove ai content credentials from image" at 0% from position 7.8. The
title led with "EXIF metadata", a phrase that appears in none of the top
queries, so the snippet never matched the intent behind the impressions.

SEO
- Title, description and H1 rebuilt around "remove content credentials from
  an image"; EXIF kept as a secondary term.
- Added a how-to section and a nine-question FAQ answering the question
  queries that had no content behind them, including the LinkedIn AI label
  and the Instagram AI tag.
- Structured data as an @graph: WebSite (alternateName "Untrace AI" for the
  unserved brand query), Organization, WebApplication, HowTo, FAQPage.
- Fixed sitemap.xml, which pointed at /untrace/ — a URL that does not exist.
- Regenerated the Open Graph image to match the new design.

Design
- Vendored the design system at src/tokens.css and composed the app from it.
  The old styling broke most of its rules: gradients, font weights 800 and
  900, raw #2563eb, Inter, and emoji as the only status signal.
- Reworked the tool into a Scan / Review / Download flow that lists what it
  found before changing anything, with the primary action pinned within
  thumb reach on small screens.
- Dark by default with a light theme, applied before first paint so the page
  never flashes the wrong surface.
- Replaced the floating donation widget, which painted an off-token circle
  over the page and covered the mobile action bar, with a footer link.

Structure
- Moved detection into src/lib/metadata.js and removal into src/lib/clean.js;
  the canvas callbacks are now a promise chain.
- Dropped Tailwind and PostCSS. Both were configured twice, and no Tailwind
  utility was used. Stylesheet is 6.2 kB gzipped with the whole system in it.

Fixes
- The stepper never advanced: stepState(index) read `current` from the
  closure, which Svelte 4 cannot track as a template dependency.
- The cleaner's fallback returned the original, uncleaned file while the UI
  reported "All EXIF metadata removed". It now reports the failure instead.

Verified against a JPEG carrying EXIF, GPS, XMP and an APP11 JUMBF C2PA
manifest: the output retains only APP0 and the sRGB ICC profile, with every
provenance marker gone.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018pRSdR57Ze9M2meDfYZgYE

src/lib/Icon.svelte

@@ -0,0 +1,52 @@
+<script>
+  /**
+   * Single stroke-icon set. Icons inherit currentColor and are decorative by
+   * default — every one of them sits next to a text label.
+   */
+  export let name;
+  export let size = "md";
+
+  const paths = {
+    upload:
+      "M12 16V4m0 0L8 8m4-4 4 4M4 15v2a3 3 0 0 0 3 3h10a3 3 0 0 0 3-3v-2",
+    shield: "M12 3l7 3v6c0 4-3 7-7 8-4-1-7-4-7-8V6l7-3Zm-2.5 8.5 2 2 3.5-3.5",
+    download: "M12 4v11m0 0-4-4m4 4 4-4M5 19h14",
+    sparkle:
+      "M12 3v4m0 10v4M3 12h4m10 0h4M6.2 6.2l2.6 2.6m6.4 6.4 2.6 2.6m0-11.6-2.6 2.6m-6.4 6.4-2.6 2.6",
+    pin: "M12 21s7-5.4 7-11a7 7 0 1 0-14 0c0 5.6 7 11 7 11Zm0-8.5a2.5 2.5 0 1 0 0-5 2.5 2.5 0 0 0 0 5Z",
+    camera:
+      "M4 8h3l1.5-2h7L17 8h3v11H4V8Zm8 3.5a3.5 3.5 0 1 0 0 7 3.5 3.5 0 0 0 0-7Z",
+    clock: "M12 21a9 9 0 1 0 0-18 9 9 0 0 0 0 18Zm0-14v5l3.5 2",
+    file: "M6 3h8l4 4v14H6V3Zm8 0v4h4M9 12h6M9 16h6",
+    chevron: "m6 9 6 6 6-6",
+    sun: "M12 17a5 5 0 1 0 0-10 5 5 0 0 0 0 10Zm0-14v2m0 14v2M3 12h2m14 0h2M5.6 5.6l1.4 1.4m10 10 1.4 1.4m0-12.8-1.4 1.4m-10 10-1.4 1.4",
+    moon: "M20 14.5A8.5 8.5 0 0 1 9.5 4a8.5 8.5 0 1 0 10.5 10.5Z",
+    github:
+      "M9 19c-4 1.4-4-2.1-6-2.6m12 5v-3.5c0-1 .1-1.4-.5-2 2.8-.3 5.5-1.4 5.5-6a4.7 4.7 0 0 0-1.3-3.2 4.3 4.3 0 0 0-.1-3.3s-1.1-.3-3.5 1.3a12 12 0 0 0-6.2 0C6.5 3.1 5.4 3.4 5.4 3.4a4.3 4.3 0 0 0-.1 3.3A4.7 4.7 0 0 0 4 9.9c0 4.6 2.7 5.7 5.5 6-.6.6-.6 1.2-.5 2V21",
+    refresh: "M20 11a8 8 0 1 0-.9 4.5M20 5v6h-6",
+    close: "m6 6 12 12M18 6 6 18",
+    check: "m5 13 4 4L19 7",
+    scan: "M4 8V6a2 2 0 0 1 2-2h2m8 0h2a2 2 0 0 1 2 2v2m0 8v2a2 2 0 0 1-2 2h-2m-8 0H6a2 2 0 0 1-2-2v-2m0-4h16",
+    lock: "M7 11V8a5 5 0 0 1 10 0v3m-11 0h12v9H6v-9Z",
+    image:
+      "M4 5h16v14H4V5Zm0 10 4.5-4.5 4 4L15 12l5 5",
+  };
+
+  const boxes = { sm: "16", md: "20", lg: "24" };
+  $: box = boxes[size] || boxes.md;
+</script>
+
+<svg
+  width={box}
+  height={box}
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="1.6"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+  aria-hidden="true"
+  focusable="false"
+>
+  <path d={paths[name]} />
+</svg>