Refactor Docker setup for environment flexibility and dev support

Moved environment variables to .env.template for better management and updated docker-compose files to use them. Added separate docker-compose.dev.yml for development, a Makefile for streamlined commands, and split backend Dockerfile into development and production stages. Updated .gitignore to include new changes.

.gitignore

@@ -262,6 +262,8 @@ celerybeat.pid
 
 # Environments
 .env
+.env.*
+!.env.template
 .venv
 env/
 venv/
@@ -300,3 +302,6 @@ cython_debug/
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
 .idea/
 *.iml
+
+# Docker volumes
+postgres_data*/