feat: add admin dashboard backend and deployment workflow

build.gradle.kts

@@ -31,6 +31,8 @@ dependencies {
     implementation("org.springframework.boot:spring-boot-starter-data-redis")
     implementation("org.springframework.boot:spring-boot-starter-validation")
     implementation("org.springframework.boot:spring-boot-starter-mail")
+    implementation("org.flywaydb:flyway-core")
+    implementation("org.flywaydb:flyway-database-postgresql")
     implementation("io.github.cdimascio:dotenv-java:3.0.0")
 
     // 2. Kotlin Modules
@@ -59,6 +61,7 @@ dependencies {
     testImplementation("org.springframework.boot:spring-boot-starter-test")
     testImplementation("org.jetbrains.kotlin:kotlin-test-junit5")
     testImplementation("org.springframework.security:spring-security-test")
+    testRuntimeOnly("com.h2database:h2")
     testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 }
 
@@ -76,4 +79,4 @@ allOpen {
 
 tasks.withType<Test> {
     useJUnitPlatform()
-}
+}