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.

scripts/icons.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Copy Lucide icons: scripts/icons.sh name...
+set -eu
+VERSION=1.48.0
+DIR=$(mktemp -d)
+trap 'rm -rf "$DIR"' EXIT
+(cd "$DIR" && npm pack "lucide-static@$VERSION" --silent >/dev/null && tar xzf "lucide-static-$VERSION.tgz")
+cp "$DIR/package/LICENSE" assets/icons/LICENSE
+for name in "$@"; do
+  cp "$DIR/package/icons/$name.svg" "assets/icons/$name.svg"
+done