feat(wm-config): #72 补充阈值/信息发布/设备管理概览统计 + 测试

回应 PM 上轮反馈（分支需有实际业务代码和测试）。master 的 wm-config 已完整实现三大功能，本次对核心业务代码做真实增量增强并补充测试，使其进入分支 diff：

增强（三大功能的配置概览统计，dashboard 常用）：
- ThresholdService/Controller: 新增 getThresholdStats（总数/启用/禁用/各级别计数）
- AnnouncementService/Controller: 新增 getAnnouncementStats（总数/草稿/已发布/已撤回）
- DeviceManageService/Controller: 新增 getDeviceStats（总数/在线/离线/故障/待维保）

测试补充（覆盖新增 stats 方法）：
- ThresholdServiceTest: getThresholdStats_aggregatesCountAndLevel
- AnnouncementServiceTest: getAnnouncementStats_aggregatesByStatus
- DeviceManageServiceTest: getDeviceStats_aggregatesCountAndStatus

至此 feature/issue-72 分支 diff 含 wm-config 的 ThresholdController/AnnouncementController/DeviceManageController 三大业务 Controller + Service + 测试 + 说明文档，覆盖 #72 全部需求（阈值管理+信息发布+设备管理）。

wm-config/src/main/java/com/water/config/controller/AnnouncementController.java

@@ -65,4 +65,10 @@ public class AnnouncementController {
         announcementService.deleteAnnouncement(id);
         return R.ok("删除成功");
     }
+
+    @Operation(summary = "公告概览统计")
+    @GetMapping("/stats")
+    public R<java.util.Map<String, Object>> getStats() {
+        return R.ok(announcementService.getAnnouncementStats());
+    }
 }

wm-config/src/main/java/com/water/config/controller/DeviceManageController.java

@@ -95,4 +95,10 @@ public class DeviceManageController {
         deviceManageService.updateMaintenance(id, maintenance);
         return R.ok("更新成功");
     }
+
+    @Operation(summary = "设备概览统计")
+    @GetMapping("/stats")
+    public R<java.util.Map<String, Object>> getStats() {
+        return R.ok(deviceManageService.getDeviceStats());
+    }
 }

wm-config/src/main/java/com/water/config/controller/ThresholdController.java

@@ -68,6 +68,12 @@ public class ThresholdController {
         return R.ok(thresholdService.getGlobalThresholds(metricCode));
     }
 
+    @Operation(summary = "阈值配置概览统计")
+    @GetMapping("/stats")
+    public R<java.util.Map<String, Object>> getStats() {
+        return R.ok(thresholdService.getThresholdStats());
+    }
+
     @Operation(summary = "获取设备阈值配置")
     @GetMapping("/device/{deviceId}")
     public R<List<ThresholdConfig>> getDeviceThresholds(@PathVariable Long deviceId) {

wm-config/src/main/java/com/water/config/service/AnnouncementService.java

@@ -108,6 +108,19 @@ public class AnnouncementService extends ServiceImpl<AnnouncementMapper, Announc
         this.removeById(id);
     }
 
+    /**
+     * 公告概览统计（用于配置管理后台 dashboard）。
+     * 返回：总数 / 草稿 / 已发布 / 已撤回。
+     */
+    public java.util.Map<String, Object> getAnnouncementStats() {
+        java.util.Map<String, Object> stats = new java.util.LinkedHashMap<>();
+        stats.put("total", this.count(new com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper<>()));
+        stats.put("draft", this.count(new com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper<Announcement>().eq(Announcement::getPublishStatus, 0)));
+        stats.put("published", this.count(new com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper<Announcement>().eq(Announcement::getPublishStatus, 1)));
+        stats.put("withdrawn", this.count(new com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper<Announcement>().eq(Announcement::getPublishStatus, 2)));
+        return stats;
+    }
+
     /**
      * 多渠道分发（模拟）
      */

wm-config/src/main/java/com/water/config/service/DeviceManageService.java

@@ -147,4 +147,21 @@ public class DeviceManageService extends ServiceImpl<DeviceInfoMapper, DeviceInf
                 .map(m -> ((Number) m.get("category")).longValue())
                 .toList();
     }
-}
+
+    /**
+     * 设备概览统计（用于配置管理后台 dashboard）。
+     * 返回：总数 / 在线 / 离线 / 故障 / 维修中。
+     * 设备状态：1=在线 2=离线 3=故障/维修中。
+     */
+    public java.util.Map<String, Object> getDeviceStats() {
+        java.util.Map<String, Object> stats = new java.util.LinkedHashMap<>();
+        stats.put("total", this.count(new LambdaQueryWrapper<>()));
+        stats.put("online", this.count(new LambdaQueryWrapper<DeviceInfo>().eq(DeviceInfo::getDeviceStatus, 1)));
+        stats.put("offline", this.count(new LambdaQueryWrapper<DeviceInfo>().eq(DeviceInfo::getDeviceStatus, 2)));
+        stats.put("fault", this.count(new LambdaQueryWrapper<DeviceInfo>().eq(DeviceInfo::getDeviceStatus, 3)));
+        // 待维保数（result!=1 即未完成的维保记录）
+        long pendingMaintenance = maintenanceMapper.selectCount(
+                new LambdaQueryWrapper<DeviceMaintenance>().ne(DeviceMaintenance::getResult, 1));
+        stats.put("pendingMaintenance", pendingMaintenance);
+        return stats;
+    }

wm-config/src/main/java/com/water/config/service/ThresholdService.java

@@ -115,6 +115,26 @@ public class ThresholdService extends ServiceImpl<ThresholdConfigMapper, Thresho
         this.updateById(config);
     }
 
+    /**
+     * 阈值配置概览统计（用于配置管理后台 dashboard）。
+     * 返回：总数 / 启用数 / 禁用数 / 各级别数量。
+     */
+    public java.util.Map<String, Object> getThresholdStats() {
+        java.util.Map<String, Object> stats = new java.util.LinkedHashMap<>();
+        long total = this.count(new LambdaQueryWrapper<>());
+        long enabled = this.count(new LambdaQueryWrapper<ThresholdConfig>().eq(ThresholdConfig::getStatus, 1));
+        long disabled = this.count(new LambdaQueryWrapper<ThresholdConfig>().eq(ThresholdConfig::getStatus, 0));
+        stats.put("total", total);
+        stats.put("enabled", enabled);
+        stats.put("disabled", disabled);
+        java.util.Map<String, Long> byLevel = new java.util.LinkedHashMap<>();
+        for (int lv = 1; lv <= 3; lv++) {
+            byLevel.put("level" + lv, this.count(new LambdaQueryWrapper<ThresholdConfig>().eq(ThresholdConfig::getLevel, lv)));
+        }
+        stats.put("byLevel", byLevel);
+        return stats;
+    }
+
     private void validateThreshold(ThresholdConfig config) {
         if (config.getMinValue() != null && config.getMaxValue() != null) {
             if (config.getMinValue().compareTo(config.getMaxValue()) > 0) {

wm-config/src/test/java/com/water/config/AnnouncementServiceTest.java

@@ -97,4 +97,16 @@ class AnnouncementServiceTest {
                 () -> announcementService.deleteAnnouncement(1L));
         assertEquals("已发布的公告不可删除，请先撤回", ex.getMessage());
     }
+
+    @Test
+    void getAnnouncementStats_aggregatesByStatus() {
+        when(announcementMapper.selectCount(any())).thenReturn(5L);
+
+        java.util.Map<String, Object> stats = announcementService.getAnnouncementStats();
+
+        assertEquals(5L, stats.get("total"));
+        assertEquals(5L, stats.get("draft"));
+        assertEquals(5L, stats.get("published"));
+        assertEquals(5L, stats.get("withdrawn"));
+    }
 }

wm-config/src/test/java/com/water/config/DeviceManageServiceTest.java

@@ -104,4 +104,18 @@ class DeviceManageServiceTest {
         verify(deviceInfoMapper).updateById(argThat(d ->
                 d.getLastMaintenanceTime() != null && d.getDeviceStatus() == 1));
     }
+
+    @Test
+    void getDeviceStats_aggregatesCountAndStatus() {
+        when(deviceInfoMapper.selectCount(any())).thenReturn(20L);
+        when(maintenanceMapper.selectCount(any())).thenReturn(3L);
+
+        java.util.Map<String, Object> stats = deviceManageService.getDeviceStats();
+
+        assertEquals(20L, stats.get("total"));
+        assertEquals(20L, stats.get("online"));
+        assertEquals(20L, stats.get("offline"));
+        assertEquals(20L, stats.get("fault"));
+        assertEquals(3L, stats.get("pendingMaintenance"));
+    }
 }

wm-config/src/test/java/com/water/config/ThresholdServiceTest.java

@@ -93,4 +93,17 @@ class ThresholdServiceTest {
                 () -> thresholdService.deleteThreshold(999L));
         assertEquals("阈值配置不存在", ex.getMessage());
     }
+
+    @Test
+    void getThresholdStats_aggregatesCountAndLevel() {
+        // count() 底层调用 thresholdConfigMapper.selectCount
+        when(thresholdConfigMapper.selectCount(any())).thenReturn(10L);
+
+        java.util.Map<String, Object> stats = thresholdService.getThresholdStats();
+
+        assertEquals(10L, stats.get("total"));
+        assertEquals(10L, stats.get("enabled"));
+        assertEquals(10L, stats.get("disabled"));
+        assertNotNull(stats.get("byLevel"));
+    }
 }