fix: 修复课程ID拼接逻辑，添加tcid2可选参数

在多个组件中统一修改cid参数的拼接逻辑，当tcid2存在时将其拼接到id后。这解决了当需要额外课程ID参数时无法正确传递的问题。

src/components/easy2/studyStudent.vue

@@ -21973,7 +21973,7 @@ export default {
       let params = [
         {
           uid: this.userid,
-          cid: this.id,
+          cid: this.id + (this.tcid2 || ''),
           type: "2",
           time: time
         }

src/components/easy3/studyStudent.vue

@@ -17385,7 +17385,7 @@ export default {
       let params = [
         {
           uid: this.userid,
-          cid: this.id,
+          cid: this.id + (this.tcid2 || ''),
           type: "2",
           time: time,
         },

src/components/pptEasyClass/index.vue

@@ -515,7 +515,7 @@ export default {
       let params = [
         {
           uid: this.userid,
-          cid: this.id,
+          cid: this.id + (this.tcid2 || ''),
           type: "2",
           time: time,
         },

src/components/studyStudent.vue

@@ -17319,7 +17319,7 @@ export default {
       let params = [
         {
           uid: this.userid,
-          cid: this.id,
+          cid: this.id + (this.tcid2 || ''),,
           type: "2",
           time: time,
         },