feat(wm-dma): #59 DMA分区计量与漏损分析

- 新增 wm-dma 模块
- Entity: DmaZone, DmaMeter, DmaFlowRecord, DmaLeakageAnalysis, WaterBalance
- Mapper + Service + Controller（18个端点）
- DMA分区管理: 分区层级定义(CRUD) + 区域划分 + 关联设备 + 树形结构
- 分区计量: 各分区进出水量汇总 + 最小夜间流量(MNF)分析 + 流量趋势
- 漏损分析: 产销差计算 + 漏损率评估 + 趋势分析 + 报警
- 水平衡表: 供水量/售水量/漏损量平衡分析 + IWA组成
- DDL: dma_ddl.sql
- 单元测试: 5个Service测试类（25+测试用例）

wm-dma/pom.xml

@@ -0,0 +1,80 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>com.water</groupId>
+        <artifactId>wm-parent</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+    <artifactId>wm-dma</artifactId>
+    <name>wm-dma</name>
+    <description>DMA分区计量与漏损分析模块</description>
+
+    <dependencies>
+        <!-- 公共模块 -->
+        <dependency>
+            <groupId>com.water</groupId>
+            <artifactId>wm-common</artifactId>
+        </dependency>
+
+        <!-- Web -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+
+        <!-- Nacos 服务发现 -->
+        <dependency>
+            <groupId>com.alibaba.cloud</groupId>
+            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
+        </dependency>
+
+        <!-- PostgreSQL -->
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+        </dependency>
+
+        <!-- MyBatis-Plus -->
+        <dependency>
+            <groupId>com.baomidou</groupId>
+            <artifactId>mybatis-plus-spring-boot3-starter</artifactId>
+        </dependency>
+
+        <!-- Hutool -->
+        <dependency>
+            <groupId>cn.hutool</groupId>
+            <artifactId>hutool-all</artifactId>
+        </dependency>
+
+        <!-- Knife4j OpenAPI3 -->
+        <dependency>
+            <groupId>com.github.xiaoymin</groupId>
+            <artifactId>knife4j-openapi3-jakarta-spring-boot-starter</artifactId>
+        </dependency>
+
+        <!-- Test -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+</project>