feat: add supervisor prototype with embedded frontend

scripts/build-frontend.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+WEB_DIR="$ROOT_DIR/web"
+EMBED_DIST_DIR="$ROOT_DIR/internal/static/dist"
+
+cd "$WEB_DIR"
+npm install
+npm run build
+
+rm -rf "$EMBED_DIST_DIR"
+mkdir -p "$EMBED_DIST_DIR"
+cp -R "$WEB_DIR/dist/." "$EMBED_DIST_DIR/"
+
+echo "Frontend built into $WEB_DIR/dist and copied to $EMBED_DIST_DIR"