feat: add PostgreSQL web installation wizard

oa-backend/build.gradle

@@ -21,6 +21,24 @@ repositories {
     mavenCentral()
 }
 
+sourceSets {
+    installer {
+        java.srcDirs = ['src/installer/java']
+        resources.srcDirs = ['src/installer/resources']
+    }
+    installerTest {
+        java.srcDirs = ['src/installerTest/java']
+        resources.srcDirs = ['src/installerTest/resources']
+        compileClasspath += sourceSets.installer.output
+        runtimeClasspath += sourceSets.installer.output
+    }
+}
+
+configurations {
+    installerTestImplementation.extendsFrom testImplementation, installerImplementation
+    installerTestRuntimeOnly.extendsFrom testRuntimeOnly, installerRuntimeOnly
+}
+
 dependencies {
     implementation 'org.springframework.boot:spring-boot-starter-web'
     implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
@@ -48,12 +66,47 @@ dependencies {
     implementation 'org.jsoup:jsoup:1.22.2'
 
     testImplementation 'org.springframework.boot:spring-boot-starter-test'
+
+    installerImplementation 'org.springframework.boot:spring-boot-starter-web'
+    installerImplementation 'org.springframework.boot:spring-boot-starter-validation'
+    installerImplementation 'org.flywaydb:flyway-core:10.22.0'
+    installerRuntimeOnly 'org.flywaydb:flyway-database-postgresql:10.22.0'
+    installerRuntimeOnly 'org.postgresql:postgresql'
 }
 
 tasks.named('test') {
     useJUnitPlatform()
 }
 
+tasks.named('processInstallerResources') {
+    from('src/main/resources') {
+        include 'db/migration/postgresql/**'
+    }
+}
+
+tasks.register('installerTest', Test) {
+    description = 'Runs tests for the standalone web installer.'
+    group = 'verification'
+    testClassesDirs = sourceSets.installerTest.output.classesDirs
+    classpath = sourceSets.installerTest.runtimeClasspath
+    useJUnitPlatform()
+}
+
+tasks.register('installerBootJar', org.springframework.boot.gradle.tasks.bundling.BootJar) {
+    description = 'Builds the standalone first-run web installer.'
+    group = 'build'
+    archiveBaseName = 'kaidi-erp-installer'
+    archiveVersion = project.version
+    mainClass = 'com.kaidi.oa.install.InstallerApplication'
+    targetJavaVersion = JavaVersion.VERSION_17
+    classpath = sourceSets.installer.runtimeClasspath
+    dependsOn tasks.named('installerClasses')
+}
+
+tasks.named('check') {
+    dependsOn tasks.named('installerTest')
+}
+
 springBoot {
     buildInfo()
 }