Backend refactoring updates

- Update Docker compose debug configuration
- Update backend documentation
- Update tasks documentation
- Update backend config module

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Docker/compose.debug.yml

@@ -61,6 +61,9 @@ services:
       BANGUI_LOG_LEVEL: "debug"
       BANGUI_SESSION_SECRET: "${BANGUI_SESSION_SECRET:-dev-secret-do-not-use-in-production}"
       BANGUI_TIMEZONE: "${BANGUI_TIMEZONE:-UTC}"
+      # Secure=false is intentional for local HTTP development.
+      # In production, Secure=true prevents session cookies over unencrypted HTTP.
+      BANGUI_SESSION_COOKIE_SECURE: "false"
     volumes:
       - ../backend/app:/app/app:z
       - ../fail2ban-master:/app/fail2ban-master:ro,z