[TC-221]: init template-backend-service (#1)

https://eva.avroid.tech/desk/cards?obj=Task:TC-221

Начальная версия сервиса-шаблона

Co-authored-by: Nadezhda <nadezhda.lavrentieva@avroid.team>
Reviewed-on: https://git.avroid.tech/Templates/template-backend-service/pulls/1
Reviewed-by: Victor Stratov <victor.stratov@avroid.tech>

local.env.example

@@ -0,0 +1,13 @@
+POSTGRES_USER=test
+POSTGRES_PASSWORD=test
+POSTGRES_HOST=cloud-postgres.avroid.cloud
+POSTGRES_DB=messenger
+POSTGRES_PORT=5432
+
+SCYLLADB_HOST=cloud-scylla.avroid.cloud
+SCYLLADB_PORT=9042
+SCYLLADB_USER=test
+SCYLLADB_PASSWORD=test
+SCYLLADB_KEYSPACE=messenger
+
+PORT=8000