feat(website): add the fl.narl.io site

Astro site for the suite: a home page with the plugin cards, install
steps, principles, the metalwork names and the ideas on the bench, one
page per plugin, and the Impressum and privacy policy. Plugin names,
versions, download links and editor previews come from the catalog, the
wrapper manifests and docs/*/assets at build time.

Served by unprivileged nginx in Docker behind Traefik on fl.narl.io,
the same setup as proton.narl.io: no access logs, CSP 'self', no
JavaScript, legal pages filled from the environment at start.

website/src/components/Bench.astro

@@ -0,0 +1,80 @@
+---
+import { IDEAS, REPO } from '../data/plugins';
+---
+
+<section id="bench" class="section">
+  <div class="container">
+    <div class="section-head">
+      <p class="eyebrow">On the bench</p>
+      <h2>What could come next</h2>
+      <p>
+        Ideas from the <a href={`${REPO}/src/branch/main/docs/ideas.md`}>ideas list</a>, each written against a problem
+        seen in bass-music production. Most of the new ones are about texture. These are ideas, not promises.
+      </p>
+    </div>
+    <ul class="grid" role="list">
+      {
+        IDEAS.map((idea) => (
+          <li class={idea.texture ? 'texture' : undefined}>
+            <div class="head">
+              <h3>{idea.name}</h3>
+              {idea.texture && <span class="badge badge-accent">Texture</span>}
+            </div>
+            <p class="label">{idea.role}</p>
+            <p class="text">{idea.text}</p>
+          </li>
+        ))
+      }
+    </ul>
+  </div>
+</section>
+
+<style>
+  .grid {
+    display: grid;
+    grid-template-columns: repeat(3, minmax(0, 1fr));
+    gap: 1rem;
+    margin: 0;
+    padding: 0;
+    list-style: none;
+  }
+
+  li {
+    display: grid;
+    align-content: start;
+    gap: 0.45rem;
+    padding: 1.4rem 1.5rem 1.5rem;
+    border: 1px dashed var(--line-strong);
+    border-radius: var(--radius);
+    background: rgb(255 255 255 / 0.012);
+  }
+
+  .head {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    gap: 1rem;
+  }
+
+  h3 {
+    font-size: 1.4rem;
+    letter-spacing: 0.06em;
+    text-transform: uppercase;
+  }
+
+  .text {
+    font-size: 0.975rem;
+  }
+
+  @media (max-width: 960px) {
+    .grid {
+      grid-template-columns: repeat(2, minmax(0, 1fr));
+    }
+  }
+
+  @media (max-width: 600px) {
+    .grid {
+      grid-template-columns: 1fr;
+    }
+  }
+</style>