[MINOR] feat(dashboard/coordinator): Display total number of applications in dashboard (#2031)

### What changes are proposed in this pull request?

Display the total number of applications in the dashboard and update the original `total app num` to `current app num`.

### Why are these changes needed?

We want to view the number of running and completed applications from the beginning until now.

### Does this PR introduce _any_ user-facing changes?

- Display the total number of applications in the dashboard
- Update the original `total app num` to `current app num`

### How was this patch tested?

Start the cluster, run a Spark application, and check the dashboard.

<img width="683" alt="image" src="https://github.com/user-attachments/assets/e4aa1c93-b329-4891-844f-f89d29ee7a8b">

Author: maobaolong

coordinator/src/main/java/org/apache/uniffle/coordinator/web/resource/ApplicationResource.java

@@ -36,6 +36,7 @@
 import org.apache.uniffle.common.web.resource.Response;
 import org.apache.uniffle.coordinator.AppInfo;
 import org.apache.uniffle.coordinator.ApplicationManager;
+import org.apache.uniffle.coordinator.metric.CoordinatorMetrics;
 import org.apache.uniffle.coordinator.web.vo.AppInfoVO;
 import org.apache.uniffle.coordinator.web.vo.UserAppNumVO;
 
@@ -51,6 +52,7 @@ public Response<Map<String, Integer>> getAppTotality() {
         () -> {
           Map<String, Integer> appTotalityMap = Maps.newHashMap();
           appTotalityMap.put("appTotality", getApplicationManager().getAppIds().size());
+          appTotalityMap.put("appCurrent", (int) CoordinatorMetrics.counterTotalAppNum.get());
           return appTotalityMap;
         });
   }

dashboard/src/main/webapp/src/mock/applicationpage.js

@@ -18,7 +18,7 @@
 import Mock from 'mockjs'
 
 Mock.mock(/\/app\/total/, 'get', function (options) {
-  return { code: 0, data: { appTotality: 10 }, errMsg: 'success' }
+  return { code: 0, data: { appTotality: 10, appCurrent: 10 }, errMsg: 'success' }
 })
 
 Mock.mock(/\/app\/appInfos/, 'get', function (options) {

dashboard/src/main/webapp/src/pages/ApplicationPage.vue

@@ -28,6 +28,16 @@
           <div class="appcnt">{{ pageData.apptotal.appTotality }}</div>
         </el-card>
       </el-col>
+      <el-col :span="4">
+        <el-card class="box-card" shadow="hover">
+          <template #header>
+            <div class="card-header">
+              <span class="cardtile">APPS CURRENT TOTAL</span>
+            </div>
+          </template>
+          <div class="appcnt">{{ pageData.apptotal.appCurrent }}</div>
+        </el-card>
+      </el-col>
     </el-row>
     <el-divider />
     <el-tag>User App ranking</el-tag>