Add logo, animated explainer, trust section and photo-privacy guides

Reposition around EXIF/GPS/C2PA privacy, replace dead HowTo/FAQ schema,
add three guide pages with sitemap and internal links.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/lib/Trust.svelte

@@ -0,0 +1,93 @@
+<script>
+  import Icon from "./Icon.svelte";
+
+  const checks = [
+    {
+      icon: "eye",
+      title: "Watch the network tab",
+      detail:
+        "Open your browser's developer tools, choose Network, then clean an image. No request carries your file anywhere, because there is no server to send it to.",
+    },
+    {
+      icon: "code",
+      title: "Read the source",
+      detail:
+        "Untrace is MIT licensed. The whole cleaner is one short file you can read in a few minutes.",
+    },
+    {
+      icon: "scan",
+      title: "Scan the result again",
+      detail:
+        "Drop the cleaned copy back in. It reports nothing found, and the tool re-reads every output before it offers the download.",
+    },
+  ];
+
+  const limits = [
+    "Pixels are not changed, so visual AI detectors and invisible watermarks such as SynthID can still recognise an image.",
+    "Platforms that already stored a copy of your credentials keep it. Clean the file before you upload.",
+    "Non-JPEG images are re-encoded to JPEG, so the file size and format can change.",
+    "Use it to protect your privacy. Do not use it to pass AI-generated work off as a photograph where disclosure is expected or required.",
+  ];
+</script>
+
+<section class="section" id="trust" aria-labelledby="trust-heading">
+  <div class="section-head">
+    <p class="eyebrow">Trust</p>
+    <h2 id="trust-heading">Verify it yourself, and know the limits</h2>
+    <p>
+      A privacy tool should not ask for faith. Here is how to check each claim,
+      and what Untrace cannot do.
+    </p>
+  </div>
+
+  <div class="tiles">
+    {#each checks as item}
+      <article class="tile">
+        <span class="ico"><Icon name={item.icon} /></span>
+        <h3>{item.title}</h3>
+        <p>{item.detail}</p>
+      </article>
+    {/each}
+  </div>
+
+  <div class="card limits">
+    <h3>What Untrace does not do</h3>
+    <ul>
+      {#each limits as line}
+        <li>{line}</li>
+      {/each}
+    </ul>
+  </div>
+</section>
+
+<style>
+  .section {
+    scroll-margin-top: calc(var(--topbar-h) + var(--space-4));
+  }
+
+  .ico {
+    display: inline-flex;
+    color: var(--accent);
+    margin-bottom: var(--space-2);
+  }
+
+  .limits {
+    margin-top: var(--space-4);
+    padding: var(--space-5);
+    display: grid;
+    gap: var(--space-3);
+  }
+
+  .limits h3 {
+    font-size: var(--fs-4);
+    line-height: var(--lh-4);
+    font-weight: 600;
+  }
+
+  .limits ul {
+    display: grid;
+    gap: var(--space-2);
+    padding-left: var(--space-4);
+    color: var(--text-2);
+  }
+</style>