chore: 统一环境配置，支持 .env 快速切换本地/远程基础设施

backend/mci-server/src/main/resources/application-dev.yml

@@ -1,19 +1,19 @@
 spring:
   datasource:
-    url: jdbc:mysql://localhost:3306/sino_mci?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&useSSL=false&allowPublicKeyRetrieval=true
-    username: root
-    password: root
+    url: jdbc:mysql://${MYSQL_HOST:localhost}:${MYSQL_PORT:3306}/${MYSQL_DATABASE:sino_mci}?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&useSSL=false&allowPublicKeyRetrieval=true
+    username: ${MYSQL_USER:root}
+    password: ${MYSQL_ROOT_PASSWORD:root}
     driver-class-name: com.mysql.cj.jdbc.Driver
   data:
     redis:
-      host: localhost
-      port: 6379
+      host: ${REDIS_HOST:localhost}
+      port: ${REDIS_PORT:6379}
       database: 0
   rabbitmq:
-    host: localhost
-    port: 5672
-    username: guest
-    password: guest
+    host: ${RABBITMQ_HOST:localhost}
+    port: ${RABBITMQ_AMQP_PORT:5672}
+    username: ${RABBITMQ_DEFAULT_USER:guest}
+    password: ${RABBITMQ_DEFAULT_PASS:guest}
   ai:
     openai:
       api-key: ${OPENAI_API_KEY:}