feat: conncet backend with database

backend/.gitignore

@@ -31,3 +31,5 @@ build/
 
 ### VS Code ###
 .vscode/
+.env
+env.properties

backend/src/main/resources/application.properties

@@ -1 +1,2 @@
 spring.application.name=wesal
+spring.config.import=env.properties

backend/src/main/resources/application.yml

@@ -0,0 +1,21 @@
+spring:
+  datasource:
+    url: ${DB_URL}
+    username: ${DB_USER}
+    password: ${DB_PASSWORD}
+    driver-class-name: org.postgresql.Driver
+
+  jpa:
+    hibernate:
+      ddl-auto: update
+    show-sql: true
+    properties:
+      hibernate:
+        dialect: org.hibernate.dialect.PostgreSQLDialect
+        format_sql: true
+
+  application:
+    name: wesal
+
+server:
+  port: 8080