T00 foundation: theme, motion, assets, icon, buttons, gallery

Theme tokens in light and dark with high contrast, a palette cross-fade,
motion curves and a damped spring, embedded Lucide icons with Inter and
JetBrains Mono, Icon, Button, IconButton, and a gallery that captures
its own window. Reviewed by codex gpt-6-astra (max): PASS in round 3.

assets/icons/map.svg

@@ -0,0 +1,17 @@
+<!-- @license lucide-static v1.48.0 - ISC -->
+<svg
+  class="lucide lucide-map"
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M14.106 5.553a2 2 0 0 0 1.788 0l3.659-1.83A1 1 0 0 1 21 4.619v12.764a1 1 0 0 1-.553.894l-4.553 2.277a2 2 0 0 1-1.788 0l-4.212-2.106a2 2 0 0 0-1.788 0l-3.659 1.83A1 1 0 0 1 3 19.381V6.618a1 1 0 0 1 .553-.894l4.553-2.277a2 2 0 0 1 1.788 0z" />
+  <path d="M15 5.764v15" />
+  <path d="M9 3.236v15" />
+</svg>