P1 fondation : tokens layerés, reset, thèmes (base/renovation/aep/tmip), 9 primitives Astro, pont Tailwind 4, démo kitchen sink

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

components/Footer.astro

@@ -0,0 +1,50 @@
+---
+/**
+ * Footer — pied de page commun.
+ *
+ * Slots : default (colonnes / liens), legal (ligne basse : mentions, copyright).
+ */
+---
+
+<footer class="tf-footer">
+  <div class="tf-footer__inner">
+    <div class="tf-footer__content"><slot /></div>
+    <div class="tf-footer__legal"><slot name="legal" /></div>
+  </div>
+</footer>
+
+<style>
+  .tf-footer {
+    margin-block-start: auto;
+    background: var(--bg-alt);
+    border-block-start: 1px solid var(--border);
+    color: var(--text-muted);
+    font-size: var(--fs-sm);
+  }
+
+  .tf-footer__inner {
+    max-width: var(--container-max);
+    margin-inline: auto;
+    padding-inline: var(--container-pad);
+    padding-block: var(--space-xl);
+    display: flex;
+    flex-direction: column;
+    gap: var(--space-lg);
+  }
+
+  .tf-footer__content {
+    display: flex;
+    flex-wrap: wrap;
+    gap: var(--space-lg) var(--space-2xl);
+  }
+
+  .tf-footer__legal {
+    border-block-start: 1px solid var(--border);
+    padding-block-start: var(--space-md);
+    color: var(--text-subtle);
+  }
+
+  .tf-footer__legal:empty {
+    display: none;
+  }
+</style>