add location display of Shuttle Bus (SEV)

      // --- State Management ---

      busLocations: [],

      sevLocations: [],

      busMarkers: [],

      unifiedStationsLookup: {}, // { "lng,lat": { name, routes: [{...}] } }

      allStationsGeoJSON: { type: 'FeatureCollection', features: [] },

    async fetchBusLocations() {

      try {

        const response = await axios.get(`https://bus.sustcra.com/api/v2/monitor_osm/`);

        //also fetch sev locations https://bus.sustcra.com/api/v2/monitor_sev_osm/

        const response_sev = await axios.get(`https://bus.sustcra.com/api/v2/monitor_sev_osm/`);

        this.busLocations = response.data;

        this.sevLocations = response_sev.data;

        // merge busLocations and sevLocations

        this.busLocations = this.busLocations.concat(this.sevLocations);

        const now = Date.now() / 1000;

        if (this.busLocations.length > 0 && this.busLocations[0].time_mt) {

          this.timeDrift = Math.round(now - this.busLocations[0].time_mt);

      const now = Date.now() / 1000;

      this.busLocations.forEach(bus => {

        if (now - bus.time_mt < 150) { // 只显示150秒内有数据上报的车辆

        if (now - bus.time_mt < 1200) { // 只显示120秒内有数据上报的车辆

          const busEl = document.createElement('div');

          busEl.className = 'bus-marker';

    },

    createBusInfoPopup(bus) {

      const directionMapL1 = { '0': '欣园 Joy Highland', '1': '工学院 COE' };

      const directionMapL2 = { '0': '欣园 Joy Highland', '1': '科研楼' };

      const lineNum = bus.route_code.slice(-1);

      const direction = lineNum === '1' ? directionMapL1[bus.route_dir] : directionMapL2[bus.route_dir];

      const color = lineNum === '1' ? '#f7911d': '#29abe2';

      // 配置表，每条线路单独定义方向映射 & 颜色

      const routeConfig = {

        XYBS1: {

          directions: { '0': '欣园 Joy Highland', '1': '工学院 COE' },

          color: '#f7911d'

        },

        XYBS2: {

          directions: { '0': '欣园 Joy Highland', '1': '科研楼' },

          color: '#29abe2'

        },

        SEV1: { // 新增的路线

          directions: { '-1': '' },

          color: '#7030a1'

        }

      };

      // 使用时直接查表

      const lineNum = bus.route_code;

      const config = routeConfig[bus.route_code] || {};

      const direction = config.directions?.[bus.route_dir] ?? '';

      const color = config.color ?? '#cccccc';

      const html = `

        <div class="bus-popup">

          <div class="plate">粤B${bus.id.slice(2)} (${bus.speed} km/h)</div>

          <div class="plate">${bus.id.slice(2)} (${bus.speed} km/h)</div>

          <div><span class="line-tag" style="background-color:${color}">Line ${lineNum}</span> To: <strong>${direction}</strong></div>

          <div>Next: <strong>${bus.next_station_string}</strong></div>

        </div>