feat: Implement multi-tenancy with dynamic data source routing and introduce a database management UI.

backend/src/main/resources/application.properties

@@ -1,15 +1,18 @@
 server.port=8080
 
-# PostgreSQL
+# PostgreSQL (дефолтный — для локальной разработки через Docker Compose)
 spring.datasource.url=jdbc:postgresql://db:5432/app_db
-spring.datasource.username=${POSTGRES_USER}
-spring.datasource.password=${POSTGRES_PASSWORD}
+spring.datasource.username=${POSTGRES_USER:myuser}
+spring.datasource.password=${POSTGRES_PASSWORD:supersecretpassword}
 spring.datasource.driver-class-name=org.postgresql.Driver
 
 # JPA
-spring.jpa.hibernate.ddl-auto=validate
+spring.jpa.hibernate.ddl-auto=update
 spring.jpa.show-sql=false
 spring.jpa.open-in-view=false
 
-#Eta nastroyka otvechayet za vklyucheniye vidimosti logov urovnya DEBUG v logakh BE, poka vyklyuchil chtoby ne zasoryat'. Zapisi INFO otobrazhat'sya budut
+# Мультитенантность
+app.tenants.config-path=${TENANTS_CONFIG_PATH:tenants.json}
+
 #logging.level.root=DEBUG
+