feat: initialize Gradle multi-module backend and Vite frontend

backend/gateway/build.gradle.kts

@@ -0,0 +1,40 @@
+plugins {
+    kotlin("jvm") version "2.4.10"
+    kotlin("plugin.spring") version "2.4.10"
+    id("org.springframework.boot") version "4.1.0"
+    id("io.spring.dependency-management") version "1.1.7"
+}
+
+group = "com.msksbr.imSystem"
+version = "0.1.0-SNAPSHOT"
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(21)
+    }
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation(platform("org.springframework.cloud:spring-cloud-dependencies:2025.1.2"))
+    implementation("org.springframework.cloud:spring-cloud-starter-gateway-server-webflux")
+
+    implementation("com.fasterxml.jackson.module:jackson-module-kotlin")
+    implementation("org.jetbrains.kotlin:kotlin-reflect")
+
+    testImplementation("org.springframework.boot:spring-boot-starter-test")
+    testRuntimeOnly("org.junit.platform:junit-platform-launcher")
+}
+
+kotlin {
+    compilerOptions {
+        freeCompilerArgs.addAll("-Xjsr305=strict", "-Xannotation-default-target=param-property")
+    }
+}
+
+tasks.withType<Test> {
+    useJUnitPlatform()
+}

backend/gateway/src/main/kotlin/com/im/gateway/GatewayApplication.kt

@@ -0,0 +1,11 @@
+package com.im.gateway
+
+import org.springframework.boot.autoconfigure.SpringBootApplication
+import org.springframework.boot.runApplication
+
+@SpringBootApplication
+class GatewayApplication
+
+fun main(args: Array<String>) {
+    runApplication<GatewayApplication>(*args)
+}

backend/gateway/src/main/resources/application.yml

@@ -0,0 +1,18 @@
+server:
+  port: 8080
+
+spring:
+  application:
+    name: gateway
+
+  cloud:
+    gateway:
+      routes:
+        - id: im-service
+          uri: lb://im-service
+          predicates:
+            - Path=/api/im/**
+        - id: log-service
+          uri: lb://log-service
+          predicates:
+            - Path=/api/log/**