chore: delete dead code, fix tailwind dark mode, fix title and start.sh port

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/start.sh

@@ -1,10 +1,7 @@
 #!/bin/bash
-
-# 启动开发服务器
-# 端口: 8000
-# 监听: 0.0.0.0
-
+# Start the Vite dev server.
+# Port defaults to FRONTEND_PORT env var, or 5173 if unset (matches vite.config.ts default).
 cd "$(dirname "$0")"
-
-echo "Starting dev server on http://0.0.0.0:8001"
-npx vite --host 0.0.0.0 --port 8001
+PORT="${FRONTEND_PORT:-5173}"
+echo "Starting dev server on http://0.0.0.0:${PORT}"
+npx vite --host 0.0.0.0 --port "$PORT"