task(62a18e54-9143-4263-9927-83f1631aa54c): Add M3 task management module (2.6/2.7 task lists and detail)

S-M3 deliverables: TaskApi (2.6 GetUserPlanGroup / 2.7 GetPlanGroup),
TaskModels, feature/task package (Repository/ViewModel/Workspace/Detail/ListAdapter),
layouts and resources; FeatureMount Tab.TASK mounted; placeholder TaskFragment removed.
CommitOnArchive was stuck after staging; committed by master chat as compensation.

app/src/main/kotlin/com/stec/cmd/FeatureMount.kt

@@ -2,6 +2,7 @@ package com.stec.cmd
 
 import com.stec.cmd.feature.home.ProjectWorkspaceFragment
 import com.stec.cmd.feature.mine.MineFragment
+import com.stec.cmd.feature.task.TaskWorkspaceFragment
 
 /**
  * 底部导航 5 Tab 与业务模块（功能明细表编号）的挂载点注册中心。
@@ -32,7 +33,7 @@ object FeatureMount {
     /** 挂载注册表：S1+ 替换 fragmentClass 即完成业务页挂载。 */
     val mounts: List<MountItem> = listOf(
         MountItem(Tab.HOME, ProjectWorkspaceFragment::class.java, "M2 项目工作台"),
-        MountItem(Tab.TASK, TaskFragment::class.java, "M3 任务管理"),
+        MountItem(Tab.TASK, TaskWorkspaceFragment::class.java, "M3 任务管理"),
         MountItem(Tab.COLLECT, CollectFragment::class.java, "M4+M5 数据采集"),
         MountItem(Tab.STATS, StatsFragment::class.java, "M6 统计与上传"),
         MountItem(Tab.MINE, MineFragment::class.java, "M1 我的"),